Category Archives: Copper Country Jewelry

Datolite Jewelry from Keweenaw Datolite

Caledonia Gem Red

We offer a wide selection of gemstone jewelry from Great Lakes stones, but a favorite gem of ours may be one you have never heard of. We are pleased to offer a great selection of Datolite Pendants, because it is so unique, colorful, coppery, and generally surprising. Datolite is not one of those “pretty sounding” jewelry names like Larimar or Sleeping Beauty Turquoise, but it is indeed very beautiful and exceedingly rare, particularly in bright, pastel colors that some of the mines were famous for. Datolite is a Michigan gemstone that should be better known.

Franklin

Mesnard

Quincy

Clark Mine

The old Copper Mines of Michigan’s historic Copper Country have produced colorful Datolite of which there is no comparison. We are fortunate to have hunted Datolite, and bought old collections over the last 30 years, always looking for great colors. Finding coveted, colorful Datolite today is rare because of several factors.

Caledonia

Closeup showing massive copper content. This Datolite virtually shines in the sun from the copper content.

HUNTING DATOLITE TODAY

Over the past 5 years many of the old copper spoil piles have sadly been crushed and used as road fill, both under paved roads and to stabilize forest roads for logging operations. Most of the few old mine dump piles left are privately owed and unfortunately, but understandably, in this lawsuit-happy world, the owners are hesitant to permit rock picking on their piles. Unstable rock piles can be quite hazardous and we hear of injuries every year caused by many factors. Frivolous lawsuits can totally dissuade what used to be rockhound-friendly mine owners from allowing anyone on their piles.

Copper, Calcite, and Datolite from the Central Mine.

Deleware

Gorgeous Mesnard

I have always felt that if I am collecting rocks it’s my owe damn fault if I injure myself. i always have my mind trained to automatically think “If i do this, then this might happen”, especially while climbing around on, or moving rocks. Money hungry specimen miners have even tunneled into rock spoil piles in the winter for valuable, colorful Datolite in years past.

MINERAL INFORMATION

Like most of the minerals and metals in the Keweenaw Copper Country, Datolite was formed in the amygdaloidal basalt through hydrothermal precipitation. It is associated with prehnite, epidote, native copper, calcite and a variety of zeolites. You could also say it is associated with chlorastrolite as it may be included in the greenstone, as can zeolites.

The Mohs hardness of Datolite is stated to be 5.5, but from my cutting experience, the hardness can vary even within a nodule or Datolite piece. Other minerals mixed in with Datolite can also be of different hardnesses, which makes cutting and polishing a copper-included Datolite quite challenging. A Datolite from the Keweenaw Peninsula can either form in seams or as nodules with a texture of cauliflower, with no hint of what is within. The most Datolites are white and have been found in all the Datolite collecting areas. Savvy Datolite hunters look for Nodules that have a light colored, cauliflower-looking skin and often porcelain-looking shards of white on the piles. Often what is found may indeed be some old dinnerware, but other times it is Datolite. Datolite is a Calciumborosilicate and it’s not unusual that it may resemble glass or porcelain. Some high temperature, high strength glass, such as Pyrex, is a BoroSillicate. One of the most glass-like, solid Datolite, from my experience, was found at the Isle Royale Mine #7 near the now Walmart location in Houghton. The Datolite from the Isle Royale Mine #7 has been made into very stable beads in the past, harder and higher in Silica than most other area mines. It is normally a translucent very pale white-green, but very nice blue Datolite has been found at the Isle Royale.

Quincy

Isle Royale Mine pendant and beads.

Isle Royale Mine Blue

DATOLITE COLORS

Experienced Datolite hunters are able to make educated guesses as to what mine a Datolite came from, based on color and crust. Keweenaw Datolite has long been treasured for jewelry and offers a broad spectrum of the rainbow. The Canary yellow from Keweenaw Point, the blue/greens from Centennial, and apple reds from various mines, and bright orange/yellows from the Quincy/Franklin/Mesnard mines are some of the most coveted. A great source of pictures to identify Datolite colors from different mines is Jeff Anderson’s Dwarves Treasures page. His favorite mineral is Datolite and he has sample Datolites from many locations.

My metaphysical friends tell me that Datolite can sharpen all mental abilities. I’m afraid that even though I have worked with Datolite for many years I still forget things. I tell people I’m in my “Wonder Years”; just today I wondered what day it was, where my TV tuner was, where my car was parked, and where Bonnie (wife) went to.

Even though I’ve owed this spectacular 38 Gram piece of luscious canary yellow Keweenaw Point Datolite for some time, you’ve never seen it. I have not decided what I’m going to do with it yet. High Grade Yellow Point Datolite is the most rare of Keweenaw Datolites, therefore the most valuable Datolite there is. I did not enhance this Datolite; This is exactly what it looks like.

The prices of Datolite Jewelry can vary widely based on scarcity, color, size, and quality. Remember that because of the vanishing mine dump piles, Datolite hunting is now very limited. Many prime locations of the past are long gone, buried, flooded, or ground up. These factors combine to make Datolite jewelry pieces great heirloom treasures which can be passed down through your family with their story. Many times someone will be seeking a Datolite from a certain mine because a relative had worked there many years ago. Quincy or Delaware Datolites are popular because people want to remember their tour of those mines.

Datolite pendants are very popular at Copper World, our retail outlet in Calumet. You may be able to purchase a rough Datolite there also.

Really good Datolite (jewelry) is a great investment, and like Western Turquoise, many the sources are no longer available. Any jewelry from Michigan’s Copper District is a good investment with a historic backstory, but for color and variety you can’t beat Datolite Jewelry.

Copper Banded Agates

Bonnie has a good hole dug, and is looking for little green nodules that may be Copper Agates.

I’m not too far away in my own hole.

After 20 years of searching the mine spoil piles in the Keweenaw, with great success, I have to admit one of my biggest blunders. I used to dig large holes in the what was left of the C&H pile, near Calumet, with my buddy Bill, looking for Datolites. At that time, if I came across a piece of copper while Datolite digging, I would keep it, but I would also find other Chlorite covered nodules, that we would call copper balls and just heave them out of the hole.

You would never believe whats may be inside these nodules.

Here’s the suprise.

Today these Chlorite covered nodules are coveted by collectors around the world. You guessed it–Many of these nodules we threw away were Copper Banded (Infused) Agates. Nobody knew at that time that these things would end up being valuable gemstones. Later I learned that my friend, the late John Perona and his brother knew about these agates for many years. Today, we also know that these special agates are found nowhere else in the world except in the Kearsarge Lode. The Powebic Lode to the South where the Quincy, Mesnard, and Franklin Mines resided, have not produced Copper Agates. You do not see Copper Agates in the rocks of the Fissure and Stratiform Deposits to the North either; so the Kearsarge Lode of the Calumet Conglomerate is very unique indeed.

Careful cutting is involved with these Copper Agates.

It’s been so many years that I forgot where my hole was, and the area has been tilled up a few times, so all those agates I threw out; who knows where they are. I actually looked for my old hole last time I was in the area. I clearly forgot where it was.

A diligent and alert Rockhound can still find Copper Agates in the Kearsarge Lode if they are willing to put in some work excavating and carefully observing the pieces of spoil rock that might contain nodules that read “hot” with a pinpoint metal detector. I enjoy sitting down and digging, especially in late August, after Black Fly season. It’s even better if it’s raining. These little balls of glory stand out a whole lot better in the rain. the usual scenario is you see a rock of rubble with nodules in it and try to extract them with tools.

How these agates formed is debatable, but the theory that makes the most sense is suggested by the Lynch brothers in their fine book Agates of Lake Superior. You’ll have to read the book to see what they say about Copper Infused Agates. I prefer that term over Copper Replacement Agates, but most of the time I just refer to them as “Copper Agates“.

My last trip involved some very successful Greenstone digging, but no Copper Agate hunting. I only had limited rock hunting time this trip, so I had to chose between Greenstones or Copper Agates.

Copper Agates are rarely really large, but some real sizable. Fully banded beauties, are sometimes found as large as a half dollar. I’m happy to find a dime sized one, but like Greenstones, a big hunker is very welcome, and always elicits a “WHOOP!”.

Here are most of those Cabochons from above turned intoÂ jewelry. All these are for sale at: www.snobappealjewelry.com

I do have miner friends in the area that usually have some Copper Agates for sale, so I always buy a few. I purchase these agates with the question; Can I make these better? If I believe that I can, I will take them home for a re-work before making jewelry. Most often Copper Agates are cut in half and sold as a pair, but often I take a pair and grind the rind off the outside where better banding may appear (or may not). Often, the odd shapes of these nodules do not allow working the outside rind, due to all the gaps and dips in the stones, so these I either work with what the slice has produced or just sell or trade these for specimens. Most Copper Agates are bought as specimens and not so much for jewelry.

The Kearsage Lode also produces small pastel, banded agates that have little of no copper in them, but are very fine; we refer to these as “mine agates”. When found these are also Chlorite covered, just as are the Copper Banded Agates. I take everything and sort them by removing the crust in my home shop.

I work Copper Agates using my soft wheels only with loads of water to keep them cool and, for proper lubrication, an additive is added to the water when cutting. Special grinding techniques are used also. I generally treat these Copper Infused Agates with a coating to make them tarnish resistant, rather than polishing them. The coating I use is one of my trade secrets.

I sell Copper Agate pendants on line, at art shows and within a mile of where I find them, at Copper World, in Calumet. The jewelry I make from these rare agates is spectacular, simply because the Copper Agates are spectacular. It seems as though Copper Banded Agates are becoming very popular as of late. I have a good selection now, and you should remember, the closer to Christmas, the more your choice narrows.

I hope you have sensed my frustration at having tossed out hundreds of Copper Agates. I’ve got to work on my memory, because if I get it back, I’ll be INFUSED with Copper Infused Agates.

Greenstone Jewelry, Where’d you get that big one?

Compared to a normal sized Greenstone, this one is a giant!. I can hear that little one screaming “I’m not worthy, I’m not worthy”.

Unfortunately, one of my long time friends in the Keweenaw developed some medical issues and can no longer cut rocks. On a recent trip up north, I was able to purchase some Greenstones that he will no longer be able to process into gemstones. A few were sizable.

Greenstones fill vugs in the Amygdaloidal (bubbly) basalt. These bubbles were created as gasses tried to escape from the lava as it cooled. In the Keweenaw the little bubble voids (Vugs), eventually filled with Silica (that produced Agates) or other minerals like Datolite, Thomsonite, or Greenstone. Copper and Silver also filled open areas in the basalt. Most all minerals and metals percolated up as super-heated, mineral and metal rich steams. That’s the very simple explanation of the Keweenaw lava. These lava flows were some of the most massive eruptions ever on earth. Most of the lavas in the Keweenaw simply bubbled up from giant rifts in the earth.

OK, I got off track here; so I see these Greenstone nodules in my mine rock and use small extraction tools to “pop” these out (where did that one fly off to?).

I always get excited when I work a really big Greenstone nodule. I’ve also learned not to get my hopes up too high; a lot of these big potentials turn out to be hollow or have a poor pattern.

Hidden under this pendant is a Quarter. Not the largest I’ve ever cut, but not a slouch by any means.

The back was fairly dead.

I usually grind the Chlorite husk off and see what’s inside. This particular stone had potentially nice pattern on one side, but was dead (no pattern), on the other. More than an hour later a really fine, big, Greenstone was finished. It’s now jewelry.

I wrapped that 9 gram Greenstone unisex style so anyone can wear it. At about 1″ across in all directions, it’s a fine piece. There is actually a Quarter under it, to give you an idea. I’ve cut many bigger ones, but these big ones are getting very scarce now days, as the old spoil piles are being crushed and hauled off for road fill.

I’ve been very busy cutting Greenstones lately, and sometimes I get a bit of a surprise. I thought you might appreciate a few oddballs and a couple very nice Greenstone.

A great Greenstone all the way around.

“Holy Greenstone Batman, it’s a Ninja Turtle”. Zeolite lining in depression.

Awesome! Greenstone in Patricianite.

Greenstone in Calcite

The reverse is all Calcite

There’s something unusual about the reverse.

The back side is Quartz. You can see the Chlorastrolite through the Quartz.

Nothing special, just a nice little Greenstone.

These other beauties are on the “to wrap” list or will be sold for other’s to work with. These are all from different locales and different hunts. Be sure to visit our Greenstone Pendants page and our Greenstone cabochon page to see current offerings.

It’s always a thrill when a plan comes together; and it did with this stone.

Hunting Michigan Greenstones

GREENSTONES GALORE

Thirty years ago things were different in the Keweenaw. Rock hunting sights were plentiful, and hunting was good. Today rock hunting areas are scarce, as mine spoil piles are bought up to be crushed and sold for road fill. Often logging companies purchase the piles to crush and use for logging roads. It seems to me that the Keweenaw has been pilfered of all its soil-based resources, and what is especially disturbing is that the whole area is a national historic park.

I’m setting on the base of what once was a pile of rubble far higher then full grown trees.

Much of the history of the Copper Country revolves around the mining of copper. With the disappearance of the mine waste piles, the history of the area is that much harder to experience and visualize. Most of what is left is privately owned and off limits to rock hounds, except a few times a year when sponsored events are arranged where mine owners are reimbursed for rock hounds hunting their piles.

We travel the Keweenaw every August for art shows at Eagle Harbor and Copper Harbor and our retail outlet Copper World in Calumet. (Lake Superior Magazine listed Copper World at the top Michigan gift shop for the sixth year in a row! (It is great to be represented at such a fine store).

At the campground, sorting what to take and what to leave. We really could not tell until we washed the mud off them.

Took these home. I will either cut them out or hammer them out.

What Greenstone look like after being extracting from the mine rock.

Often Greenstone have fallen out of the rocks and can be found just laying on the ground or in the piles.

If you want to hunt Greenstones or other copper-related minerals currently two organized rock hunt opportunities are available, arranged by the Seaman Mineral Museum, and by the Copper Country Rock Club. The groups arrange to have the mine waste piles bulldozed and participants who have paid the fee get to have first look at trying to find a new treasure that has been buried for decades (or eons) and brought to the surface by the bulldozer.Â Â We have participated in many of these hunts over the years. Sometimes they are worthwhile and sometimes they are a disappointment.

Clearly there is Copper in this one.

Rain is the rock hounds friend, rinsing the dirt off the rock that was stirred up in the recent few weeks of organized hunts. This year we were able to go hunting between art shows on a couple of rainy days. We were successful in finding greenstones, datolite, prehnite, and native copper. Often we pick up muddy things that look of interest, and after cleaning may turn out to be wonderful finds. And sometimes a promising rock is disappointing. You often don’t know what you have until you do the lapidary work.

Dopping begins the grinding and polishing process. I use, nails, screws, rivets and glue the stones on to the Dops. Others use dopping wax.

Keweenaw Greenstones are especially tricky, they may have no pattern, or they may break apart. What appears to be a fine Greenstone, as you work it, may in fact be hollow; you have something, than you have nothing. Working Michigan State Gem Greenstones to their maximum potential takes a gentle hand, and lots of patience. When polishing a large stone I get excited if it has a great alligator pattern and a chatoyant surface. The other thing about greenstones is that it dictates how it can be cut. Sometimes the pattern layer is so thin, that you have to know when to stop grinding. YouÂ may or may not be able to eliminate inclusions that distract from a perfect stone. Â Those I give to teachers that teach Earth Sciences. Only experience tells you if you have the stone perfect, or if you can make it better. They are a uniquely difficult gemstone to get right, and in general the highest quality GreenstonesÂ can be pricey.Â Many greenstones must be cut before I get a one that has the qualities expected in a gem. If you have a large stone you want to have polished, be sure to have someone cut it that has experienced in cutting Greenstones. I’ve seen $1000 Greenstones ruined because the person cutting it did not know what they were doing. I liken some Greenstones to Fire Agate; You have to know when to stop, and there is no room for error.

Another truth is that Most Michiganders have never personally seen an Isle Royale Greenstone, and I have been asked things like “is that a Green Petoskey Stone?” or they’ll say things like “I found one of them on Lake Michigan” NOT! One of these , usually small stoned, would never survive the glacial transportation. A picture does not do justice to the lovely, silky, Chatoyancy or Michigan’s State Gemstone. You have to see one in person to appreciate it. They’re like an alligator wearing a shear silky robe.

This is a “Broll”. It’s made my life easier. Do a search if you are interested; it’ll save me answering a bunch of questions. This picture was takenon a Petoskey Stone Hunt.

Bonnie always takes home a couple garden rocks, and our Broll is a handy tool for carrying rocks back to the car. For those who haven’t seen one, you can see and buy a Broll online; we take it on all our rock hunts.

A beautiful Thomsonite flowered Greenstone from the Phoenix Mine.

People look for us at the art shows and bring something that they have found to have a special piece of jewelry made for them. Cutting their rocks and making their jewelry keeps me busy for a while.

Even though gemstone hunting is not what it once was, we still enjoy our trips. The art shows, natural beauty, wonderful sunsets, rock hunts, pasties, Vollwerth’s hot dogs, and monk’s muffins all contribute to a vacation atmosphere while we are doing our work!

Yellow Datolite from the Delaware Mine (and Other Places)

Classic Delaware Yellow. The color is corrected in this picture to reflect the true color.

What I bought in Tucson-Part 3

Sometimes I find unusual things in odd places. Bonnie was perusing my friend Gary Wilson’s booth at one of the major Tucson Shows, when she spotted three slices of Yellow Datolite. All were from the same piece of Datolite. Yellow is one of the most sought after colors in Datolite.

Most Keweenaw Datolite sports a wide range of coloration caused from small copper inclusions ranging from orange to red to pink. White is the most common color and was found in all the Keweenaw mines. Yellow Datolite is rarer, getting it’s color from manganese, which is not as abundant as copper. The finest bright yellow is found around the tip of the Keweenaw Peninsula, the northernmost land in Michigan. Fine yellow Datolite has been found at the Quincy, Franklin, and Mesnard mines. Often these three mines had mixtures of colors that looked like they were stirred together, and not quite mixed enough. These three mines as well as the Centennial (blue) are historically the gourmet Datolite collectors Favorites.

Yellows are also found in other mines including the Delaware and Connecticut. Often, Datolite colors can be fairly specific to one mine, and yellow shades are ones you can often determine the source from the hue of the stone, but we Datolite collectors can sometimes be fooled by yellows.

The Delaware Datolite cut into three pieces. I have a couple more to wrap.

The king of yellow Datolite; The ultra rare Kewenaw Point.

The Quincy Mine produced a wonderful caramel yeollow. This little beauty I made for this blog.

The Delaware mine tailings pile has all been hauled away and that historic site for hunting Datolite is now extinct. Enjoy these Datolites while they are still available.

Can you make jewelry from Keweenaw Prehnite?

Botrioidal Keweenaw Prehnite rough

A thin Patricianite seam. Yes, that copper sheet is embedded in it.

Patricianite Rough (Non-seam material)

Here’s a little trivia you may not know about the mineral Prehnite: The first modern mineral to be named for a person was…..PREHNITE. Abraham Gottlob Werner of the Freiberg Mining Academy, was a popular teacher, but is also credited for delaying the advance of Geology by insisting upon wrong concepts on the origin of rocks and minerals. He WAS successful in classifying minerals. Werner named the mineral Prehnite after Col. von Prehn after von Prehn brought the mineral to Europe from the Cape of Good Hope (1783), where he found it.

I love rock trivia. I found this knowledge in a 45 year old book I have. Let’s take a look at some of the variations of Keweenaw Prehnite. Where possible I will show the cabochon before it became jewelry.

This Patricianite sports loads of Copper. I think it would look good as jewelry.

Why, yes indeed it did look good as jewelry.

Prehnite is a Copper Associate Mineral in Copper Country. Much of the Prehnite contains copper dust that changes green Prehnite to pink Prehnite. Other inclusions in Prehnite also produce a plethora of colors. Zeolites sometimes mix with Prehnite (A calcium Aluminum Silicate) in the Keweenaw and produce feathery eyes and patterns. Copper and Chlorite included Prehnite is sometimes referred to as “Patricianite” by copper country locals.

Pastel Patricianite with small Copper Inclusions. This was a massive chunk before slabbing.

Another one that made great jewelry.

Pastel Prehnites roll up on the beaches all along the west side of the Keweenaw Peninsula. While looking for agates, beachcombers may see a bright pink stone shimmering among other dull stones. Pick it up, it might be a coppery beauty. These nuggets can have pink and green together, sometimes even purple tones. I have found Prehnite in piles of materials cleared from road construction not far from Calumet. Prehnites are also gleaned from rock spoil piles at some mines. I have a secret hole that I also occasionally excavate for Prehnites. The best Prehnite has always been associated with Austraiia, but gemmy pastel green Keweenaw Prehnite with Copper inclusions, in my opinion, gives the Aussie stuff a run for the money.

Prehnite with Copper. This is the high quality stuff often found in slim seams.

Prehnite with very little Copper. This is the high quality stuff often found in slim seams.

Prehnite is sometimes referred to as U.P. Thomsonite because its’ appearance often mimics Thomsonite, with eyes, radiating sprays, and variegated inclusions. Some Prehnite is difficult to tell from Thomsonite, or other Zeolites, and for many years Prehnite was thought to be a Zeolite. It was determined by Analysis by Michigan Tech geologists that Prehnite is not related to the Zeolites, but can be associated with Zeolites. Prehnite is a Calcium Alumosilicate. More confusing is when Zeoiles mix with Prehnite and make the Prehnite look exactly like Thomsonite. Thomsonte is almost an exclusive American Gemstone (more trivia for you guys), Prehnite is much more scattered and can be found in numerous locales around the world.

Loads of Copper in this Prehnite. Mine seam material.

Loads of Copper runs through this Prehnite, a mine seam material.

A beautiful oddball dug from a hole somewhere in the Keweenaw Peninsula. Prehnite, assorted Zeolite and other stuff. A beautiful mix, don’t you think?

The Apple Green Prehnite from the Keweenaw can be found as small round Crystals, but in most cases as slim veins in the Amydaloidal basalt. I have found much of the Prehnite in my collection in veins that are less that one inch. The Prehnite seems to form within a void from the outside in, meeting in the middle of the void. After extracting the Prenite bearing host basalt, I usually split the Prehnite where it meets in the middle. I can then use both sides to make beautify cabochons and jewelry. I like when the Prehnite sometimes does not completely close off in the middle of the seam, leaving a void where Prehnite Crystals form in a drusy. Remember it is often possible to find copper within the U.P. Prehnite. Copper can be found included in most every Keweenaw mineral.

The Seaman Mineral Museum, in Houghton, Michigan, has some wonderful, large Prehnite crystals found by miners over the years. Knowing that a Mine Captain or Superintendant or other mine management person was a mineral collector, the miners could score some points by turning these specimens over to them. Some of the finest specimens at the Seaman Museum were from these historic collections donated to the museum by heirs or willed by the owners of the collections.. Two of the most prolific collectors were J.T. Reeder, who clerked at several different mines, and L.L. Hubbard who discovered the Champion Mine and served as general manager of the mine. It is interesting to read and learn about these early collectors. Hubbard willed some of his collection to the University of Michigan, and recently the U of M has given many Copper Country specimens, from historic collections, to the Seaman Museum.

Many rockhounds overlook Prehnite or Patricianite while rock collecting in the Keweenaw. it’s one of my favorites and I never miss a chance to pick up nice pieces. So what do you think? Does Prehnite/Patricianite make good jewelry? You are invited to visit my jewelry pages to see the variety created from Keweenaw Treasures, especially Prehnite .

Datolite: One of the Keweenaw’s Colorful Mineral Treasures

I tried to do justice to a customer’s Yellow Keweenaw Point Datolite. earring and bracelet set.

You already know that Datolite is my favorite Calcium-Borosililicate. I just love the way that flows off the tougue, and it sort of makes you look smart when you say it. Datolite commonly occurs in the the Keweenaw in the Copper deposit host rocks in veins and vesicles. We also find Datolite in mine waste piles, often in the form of round, Califlower-looking crystals that have popped out of the host rocks left from mining Copper. If you find Datolite in the Keweenaw, you can be assured there is copper nearby..

Quincy Yellow

Franklin or Mesnard (?)

White Datolite can be from anywhere. This one containing classic Datolite Crystals.

The most common color of Datolite is white, and can be found in all the copper deposits in the Keweenaw. Pink is the second most common color. A close microscopic study of pink Datolite will reveal the pink hue is the result of micro copper within the stone. the darker the pink, the more copper in the Datolite.

Copper is the star in these three I’ve been saving for a personal piece of jewelry. From right clockwise: Keweenaw point Yellow Datolite, Copper Replacement Agate (Kearsarge Lode), Dark Chlorastrolite with Copper.

Centennial Blue (#2 Shaft)

Copper “Lightning” in Centennial Blue

Colors in Datolite run the entire color palette. Impossibly rare is the Canary Yellow from the Keweenaw Point. Unlike most Datolite in the Keweenaw this yellow Datolite gets its’ color from manganese and not Copper. This Point deposit is primarily under water, but has been covered with green algae for quite a few years now, making it almost impossible to find in the host basalt.

Most mines, where Datolite occurs, sport particular colors in their respective Datolites. I, and many other serious Datolite hunters can make educated guesses as to where a particular Datolite might have come from. I find my friend Jeff Anderson’s website the go-to site for Datolite ID. Check it out at http://www.sailorenergy.net/Minerals/MLDatolites/MineralMainDatolitesMI.html

Another rare Datolite is the Centenial, a white Datolite stained blue-green from oxidized copper. Several hundred pounds were removed, from a muddy pocket deep in the mine, in 1962 by miners. This was all that were found, and after the mine was closed, it flooded. If you have one of these “Tidy-Bowl” colored beauties, you are fortunate indeed. All Centennial’s were either full of copper flecks, or had less copper, making them lighter blue. Some blues came from other areas, like the Phoenix Mine (Phoenix), and the Isle Royal Mine (Keweenaw County). Even though blues are found in other locales, the best blues have always been from the Centennial.

Mesnard in the classic colors Mesnard is famous for.

Quincy Caramel!

Caledonia Mine. The red is Microcline (var Adularia)

Beautiful and striking Datolite colorations came out of the Mesnard, Franklin, and the Quincy. These three mines were eventually tied together by adits. The Orange/pink/red combinations are amazing from the Franklin and the Mesnard, as is the caramel Yellow’s from the Quincy.

Datolites of all colors were prolific at the Delaware and Connecticut Mines over the years. Many of the mine waste piles, including the Delaware, have been crushed in the last few years for road fill. Finding any Copper Country mineral is not as easy as in years past, mostly because of the incessant crushing of the old mine waste piles.

Bonnie found a wonderful bag of Datolites, I obtained several years ago, in my shop. I thought you would enjoy what I’ve been doing with them.

My Datolite jewelry is very popular at Copper World in Calumet, on our website, or see us every year in August at art shows in Eagle Harbor and Copper Harbor where you can choose your jewelry (Including Datolites) in person. All the types of Datolite’s mentioned in this blog are still available from us, but are becoming depleted as people realize if they don’t get one know, they may never get the ones they want.

The Shades and Patterns of Greenstone (Chlorastrolite)

Every one of these are made from Island Stones.

Greenstone (Chlorastrolite) is the State Gem of Michigan. They are only found in the Keweenaw Peninsula and on Isle Royale (harvesting Greenstones in Isle Royale National Park is prohibited), with a few rolling up on North Shore beaches. These are known facts about Greenstone; but did you know that Greenstones can be many shades of green and contain many types of inclusions?

I thought, in this month’s blog, it might be fun to show you some of the uncounted associated minerals that can be found with Greenstone. I am mostly covering the more common inclusions, but I’ll show you some uncommon inclusions also. The Greenstones were all in my possession at one time, and are from my photo collection after years of Greenstone picking and collecting.

When I write about Greenstones colors, patterns, and inclusions I am speaking of an “average” stone. If I write something in my blog on the subject of Greenstones, someone may comment to the effect that what I wrote is not always the case. “Not always the case” is one of the laws of Greenstone, as well as many Rocks and minerals of Lake Superior.

Greenstone with Silver

Greenstone with Copper. Notice very little pattern to this dark Chlorastrolite.

Rough Greenstone; Some included and some not.

Included with Thomsonite, Calcite, Copper, Datolite

Just when I think I’ve seen it all, there’s something different. Lake Superior Agates, Datolite, Prehnite, Thomsonite, and many other minerals from this area are famous for their surprises.

Greenstones from Isle Royale, in general (remember) are a lighter shade of green than those found in the Keweenaw. Isle Royale Greenstones most likely will be solidly patterned all the way through the stones, and require less skill than cutting a Keweenaw Greenstone that may have the chatoyant alligator pattern in a very thin layer, which is easily cut through. Cutting Keweenaw Greenstone is, many times, more like “erasing” the bad spots, rather than actually grinding. These Keweenaw stones may contain annoying little black dots that definitely do not enhance a Greenstone. I seldom see these dark inclusions in Isle Royale Stones. I have never been clear whether these spots are Chlorite or actually Chlorastrolite. There are other unwanted flaws that can occur in Greenstone; some I deal with, others, forget it. Only experience in Greenstone cutting can help you determine what you can deal with, and what you can’t. I could write a whole book on cutting Greenstones. Only by cutting thousands of these little buggers can you develop some expertise. You must, unfortunately, learn by your mistakes. Making mistakes was a lot easier to take years ago, when Greenstones were easier to find and far less expensive that they are today. I can never answer the question “How do you cut a Greenestone?”. The answer always boils down to the particular Greenstone you are cutting.

Island Greenstones in matrix.

Tumbling these Greenstones from Islae Royale allows weeding. Notice the Thomsonite Inclusions on may little Greenstones.

OK, I got off track there a little bit. The point I wanted to make is not only are there good inclusions in Greenstone, but there are bad ones also.

Now lets look at some of the inclusions that really enhance a Greenstone. Coming from the Copper Country, an inclusion you might expect in Greenstone is Copper. Chlorastrolite filled the small voids in the amydaloidal basalt, as does most of the minerals found in the copper country. Rarely found together, the Copper and Greenstone are so beautiful together. On a rare occasion we may even find a Greenstone with Silver in it.

Greenstone floating in Calcite with Included Copper.

Some Greenstone is almost white.

Datolite is another Copper Associated mineral that often in found in Greenstone, plain white Datolite is common, but other Datolite colors, especially pink, are also seen. Pink Datolite is always caused by micro-Copper in Datolite.

Greenstone with a heart of Thomsonite.

Greenstone in Thomsonite’s ugly cousin Natrolite.

Thomsonite, my favorite Zeolite, is found in Greenstone. You can tell Thomsonite from Datolite by it’s silky, chatoyant, look. Datolite will be more porcelinious without a silky shine. Thomsonite in Greenstone can be pink or white.

A whole garden of flowery Thomsonite.

Chlorite specks mean the Greenstone needs more work to remove them.

Copper and Silver specks in this one.

Could this be Chlorastrolite replacement of Calcite? It sure looks like it to me. The pink is Prehnite.

Greenstone containing Calcite Crystals.

Calcite is probably the most common inclusion, or you might say Greenstone is included in Calcite most of the time we see it together. When I see Greenstone in more clear Calcite, it seems to float as islands on top of the calcite. I love the three-dimensional look that is seen in Greenstone in Calcite. Commonly when Chlorastrolite is seen in Calcite, the Greenstone looks like dark, black-green lilypads instead of the more classic alligator-like pattern common to the gem. I like the lilypad look myself, but the stones do not fetch the price of a patterned Greenstone.

I have seen tiny Calcite crystals floating within the Greenstone also. It’s very nice when that happens, but most buyers of my Greenstone jewelry do not understand the rarity of this phenomenon.

$Greenstone with Cuprite is so rare it baffled the experts at the Seaman Mineral Museum\.$

Greenstone with Cuprite is so rare it baffled the experts at the Seaman Mineral Museum\.

On one occasion, I found bright red Cuprite on Greenstone. I never should have sold that one, as I’ve never seen another like it. It amazed the Director of the Seaman Mineral Museum.

Lastly I want to address the coloration and patterns of Greenstone. Greenstones can range from almost white to olive green to dark forest green. Sometimes Greenstones are so dark you’d swear they were black.

A dark Greenstone from the Central Mine. Notice the larger alligator pattern.

A dark alligator from the Central Mine.

The patterns in Greenstones vary from large alligator to tiny alligator, to dark islands, to hardly any pattern at all. I’ve seen tiny donut circles, to shimmery flower-like chatoyant circles, to just a hint of pattern. When we find an obvious Greenstone without pattern we refer to it as a “Greenstone wanna-be”. Every round pebble on a spoil pole is green, so we pick them all up, perhaps tumble them overnight in 220, and look at the batch in the morning. The Greenstones will survive, but the Chlorite balls will not.

A big. bold Greenstone with Pink prehnite from Isle Royale in the 1940’s.

A Boytrioidal Greenstone from Isle Royale. Notice the unusual green coloration.

A beautiful Island stone in mysterious green.

I’ve been cutting and polishing Greenstones for many years, and have enjoyed the differing colors and patterns in Greenstones; not all Greenstones are equal. My hope is by informing you of these details, you can come to appreciate one of the rarest gemstones on Earth. Greenstones continue to amaze and surprise me, but unfortunately the sources are diminishing.

This would be a very nice Greenstone except it contains unwanted inclusions of Chlorite. After a bit more work, this one became a real beauty.

A simple wire wrap is sometimes best.

Back in mining days, the miners never had a clue that their discarded rubble contained the lovely gem material that today is being crushed and hauled away for road fill. It’s exponentially harder today to find a nice Greenstone in the Keweenaw than it was a decade ago.

I loved this Datolite and Greenstone Pendant.

Explore our wide selection of Greenstone Cabochons, Greenstone Pendants and Greenstone Earrings as well as other jewelry from Keweenaw Minerals.

Owyhee Picture Jasper and other Great Lakes Gemstones

Can you guess why I called this pendant “Sleeping Bear”

North Shore Thomsonite

Now that the Tucson shows are done, the jewelry creation process is moving forward. Over the past week I’ve made several pieces of jewelry, especially Michigan stones, from Lake Superior Agates, Datolites, Dark-eyed Thomsonite, and a really special and amazing Laker pendant.

Yellow Snow-don’t eat it. I did not enhance the color in this at all.

Sugar and stripes.

This is why Lake Superior Agates are my favorite gemstones. This one is “Stripes in Stripes”

I love these. I called this “The Red Continent”.

I have had this particular Laker slab that shows the classic Laker reds, but also Citrine. When you find the reds and the yellows together it is surprising and fantastic!

Even I was amazed. This one is called “Lady Luck”, a unisex piece of jewelry. I test wore it and won a fifty-fifty drawing. Do you need some luck?

A really odd Waterlevel Laker with a lot going on. It is not named yet.

Other Lakers I made into pendants are so very unusual with the banded Laker floating in Sugar Quartz or with the more common sugar Quartz surrounded by the colorful laker.

Peachy-pink Mesnard Datolite.

A Yellow Quincy-Outstanding!

Colorful Datolite is always a winner, and a gorgeous Peach from Mesnard, and a Quincy Yellow are new pieces. Really nice colored Datolite is getting very hard to find. The old piles are held by private interests (not allowing hunting for liability reasons), or crushed and hauled for road fill. Any colorful Datolite demands premium prices. I’ve been advising people to buy Datolite Jewelry now, if they like it. Old stocks of Datolite are being used up.

Greenstone-Central Ex pile (when there was a pile)

Just for variety I did a North Shore Thomsonite, which is another beautiful stone from the Lake Superior Region, especially Minnesota and the Keweenaw Peninsula.

Amongst all these Michigan gemstones, why did I feature a western Owyhee Picture Jasper? Well, when we saw it at a show, it looked so much like a picture of a Michigan lakeshore. If you have ever visited Sleeping Bear National Lakeshore, you will recognize the resemblance to this beautiful Owyhee Picture Jasper. Welcome to my creative world!

Great Lakes Gemstones Make Amazing Gifts

One of the best things of the holiday season is passing along beautiful jewelry gifts to new owners. Great Lakes gemstones are the cornerstone of our selection. Our best sellers are our many amazing Isle Royle Greenstones. Our acquisition of a collection of old Greenstones found on Isle Royale over 60 years ago has enhanced our status as the webs’ go-to site for Michigan’s State Gem. Our wire-wrapped Isle Royale Greenstone pendants come with various mixes of tarnish-resistant argentium wire and 14/20 yellow gold or pink gold wire. The pink gold is especially prized for combining with the Isle Royale Greenstones that have Thomsonite inclusions. We also sell cabochons so that people can have rings or other items created just for them.

Centennial Datolite

Mohawkite

Thomsonite

Snob Appeal Jewelry is also the go-to site for any Great Lake Gemstone. We really enjoy the appreciation notes we get after Christmas from many happy new owners. Many of these stones are not widely known outside of the Great Lakes area, so when we get orders from Texas or California or other far-flung places (even Australia) we always wonder what drew them to select Datolite or Mohawkite or Thomsonite. We know these are beautiful stones, but often there is another connection, such as a family member who worked in a particular mine, or even if it was just a visit to the enchanting area.

Our selection of Lake Superior Agate pendants is Superior! We have water level agates, sagenite agates, tubes, and eyes, candy stripers, gray stones, pink, brown, “Laker” reds, even some yellows. Some have copper, some have quartz centers or even amethyst. Don loves these stones and classically wire wraps them to enhance their natural beauty and variety. Pick one to give to your favorite rock hound!

Lake Superior Agate

I thought I might show you some new jewelry especially made for Christmas.