The Coulee Rock Club, based in Wisconsin’s Driftless Area (see end paragraph), working with the Show Chair Allison and her crew, held its annual rock, mineral, fossil, and jewelry show and sale during the second weekend of June. By all accounts, the event was a resounding success, drawing an estimated attendance of ~1600—perhaps the largest turnout in recent memory. Visitors streamed through the doors from Saturday’s opening to Sunday’s close, and the vendors I spoke with seemed pleased with their sales. As rock and mineral shops continue to close across the country, shows like the Coulee event may be the best—and perhaps last—places to view genuine specimens in person and to chat with dealers and other rockhounds in an informal environment.
You just can’t beat two bucks a head complete with friendly conversation!
My “job” for the show was as a greeter and font of knowledge about all things geological, especially where to collect Lake Superior Agates: ANSWER-- examine all decorative river-derived gravel lining flower beds, sidewalks, etc. as you walk around town; 2) visit a local landscaper and obtain permission to examine their landscaping gravel; and 3) join our rock club and attend the field trips walking or canoeing the sand bars in local feeder streams. In my opinion, it is much easier to collects agates in downtown La Crosse along the Mississippi River than to scour the shorelines of Lake Superior.
Meet Mr. Castoroides, a bear-size beaver who only became extinct about 10,000 years ago.
As a greeter I was trying to attract, and visit with, the younger clientele who were tagging along with their parents or grandparents---get them interested at an early age. I was fairly successful since I brought along some of my casts of a Pleistocene Giant Beaver and a Dire Wolf along with the giant claw from the Oklahoma Allosaur. I also had a bag filled with small “pretty rocks,” mostly shiny and siliceous, as a “give-a-way” to entice their interests. Often, youngsters know a large amount of information about fossils and they like to tell anyone within earshot. Bring ‘em on; KIDS ROCK!
Buyers were waiting when the doors opened.
I am not an avid agate collector nor a lapidary, both major hobbies of many of our club members. These interests relate to our local bedrock geology—outcrops of Cambrian sandstones and Ordovician carbonates with the latter often containing siliceous vugs or nodules and at times calcite crystals, and the gravels and cobbles containing agates along the River. However, the club also sponsors exciting collecting trips to the Black Hills and adjacent outcrops, Moose Lake, MN agates, Wisconsin moonstone, agate rivers of Montana, Keokuk concretion rocks of Missouri and Iowa, amethyst quarries near Thunder Bay, Ontario, famous Native American quartzite quarries, and fluorite localities in Illinois and Kentucky. See Couleerockclub.org for information.
I prefer to visit dealers with a selection of interesting and non-common minerals—no pyrite, calcite nor quartz! And sometimes these dealers are tough to find her in the Midwest, unlike shows in my previous abode in Colorado. Therefore, I was pleasantly surprised to Find SS Rocks from up the road in Oshkosh, WI. SS Rocks hits many of the rock and mineral shows in this part off the Midwest but also has a large EBAY presence with auctions and a store (ssrocks2015). They simply have a large collection of minerals from many parts of the world and quite reasonable prices.
Several local members of the Coulee Club participated in the dealerships of the show with wares ranging from jewelry to agates to local/semi local minerals. I was most interested in a large hunk of amethyst-bearing rock collected from the quarries near Thunder Bay, Ontario, hauled back by Apryl. It certainly is more exciting than Cambrian sandstone road cuts! Jay and Jana, agate slicer and ring maker extraordinaire, worked tirelessly to clear away hundreds of specimens via the club silent auction.
A regular dealer at the Coulee Show is “Mr. Wisconsin Agate” Doug Moore from up the road in Stevens Points. Doug is a masterful agate collector and agate photographer and is known worldwide for his spectacular prints and posters, especially of those collected from Germany (over 30 trips since 2002), the Lake Superior region of the Midwest, Oregon thundereggs (a book in is the works), and Fairburn types from the Black Hills region. Check out this QR code for some of Doug’s photos.
So, one of my purchases this year from SSRocks was a nice blue mineral (I seem stuck on blue minerals), veszelyite, a hydrated copper zinc phosphate, [(Cu,Zn)2Zn(PO4)(OH)3 · 2H2O]. As a rare secondary mineral found in the oxidized zone of some polymetallic mines rich in copper and zinc. The “blue” color, often quite vivid, comes in a variety of shades from the well-known electric blue, to royal blue and cobalt blue, to turquoise blue-green, to mostly green to light blue. The crystals are vitreous to subvitreous, and rather soft (~4.5 Mohs). Larger crystals are identified as Monoclinic and flattened or elongated Prismatic. However, many specimens contain quite tiny, bladed crystals or granular aggregates and are difficult for me to locate well-formed crystals.
The matrix of the specimen consists of tiny botryoids of hemimorphite [Zn4Si2O7(OH)2 · H2O]. Note some blue veszelyite showing through. Width FOV ~ 6 mm.
Veinlet of intense blue veszelyite in a mixture of matrix hemimorphite and lighter blue veszelyite. Width FOV ~6 mm. The green botryoids are hemimorphite or perhaps cuprodongchuanite, a lead zinc copper phosphate. Width FOV ~6 mm.
A vug (~2 mm) in the matrix containing microscopic crystals of veszelyite with a partial covering of two shades of green botryoids.
Submillimeter aggregates (darkest intense blue) of flattened plates of veszelyite crystals. Best crystals I could locate and get a photo.
Veszelyite is a rare mineral and for decades most specimens, never common, came from Africa and Europe (Type Locality in Romania, 1874) although the Black Pine Mine in Montana produced what was/are the finest crystals. Then recently, in the last decade, magnificent and numerous specimens hit the market from the Dongchuan Copper District, Kunming, Yunnan, Peoples Republic of China. The Dongchuan Mine in the District is the source of my specimen.
The District is a major producer (third largest) of copper utilized by the industrial giants of China. The copper ore is found in sedimentary rock-hosted, strata-bound deposits and has been mined for centuries. One early use of the copper was to mint bronze coins (an alloy of copper and tin) during the Quig Dynasty, the last imperial dynasty of China (1644-1912). MinDat noted the District has produced 84 valid minerals including 7 types (mostly colorful tiny phosphates). It is well known as a collector’s paradise.
FYI: The Driftless Area is a topographic and cultural region that comprises southwestern Wisconsin, southeastern Minnesota, northeastern Iowa, and the extreme northwestern corner of Illinois. It was never covered by ice during the last glacial period, so the area lacks the characteristic glacial deposits known as drift. Its landscape is characterized by steep hills, forested ridges, deeply carved river valleys, and karst geology with spring-fed waterfalls and cold-water trout streams. Ecologically, the Driftless Area's flora and fauna are more closely related to those of the Great Lakes region and New England than those of the broader Midwest and central Plains regions. The rugged area near La Crosse (my home) is known as the Coulee Region due to the steep and deep canyons (coulees) cutting through the River bluffs to Base Level (the Mississippi River). Many areas in the bluffs are ~ 600 feet above the River and offer amazing views (see Grandad Bluff). Mt. La Crosse Ski area near the south edge of the city has a vertical drop of 516 feet and is a major destination in the area. It just a pretty nice place to live and enjoy life.
Above paragraph extracted from Wikipedia July 2026.
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