Despujolsite, Mallestigite, Schaurteite, Genplesite: OK, if you are honest with yourself you will admit you have never heard of these minerals. I hadn’t. And therefore you would not know that they are all hexagonal sulfates within the Fleischerite Group of minerals. But naturally there is even more about them you do not yet know but should!
At the November meeting of the Wayne County Gem and Mineral Club there was general bemoaning that the field season seemed over. That was until two members suggested that we visit the Lake Ontario shoreline on Sunday for one last outing. And so we did. In fact ten of us spent several hours walking the rocky coastline at a couple of our favorite haunts. It was our 22nd club field trip of the year, and probably our last.
Everyone likes to classify things: by shape, by color, by cost, by size. You name something to sort by, and someone is busy classifying with it. So, it should be no surprise that geologists get classified. And perhaps the first way they get labeled is as either a soft rock geologist or a hard rock geologist. No, it has nothing to do with the character of their head (although some might disagree) and it has nothing to do with their taste in music. Rather it relates to the type of rocks they study.
December is a month when many things are overdone. Stores are open 26 hours per day, sales offer discounts on discounts (or so they claim), foods have more calories and portions are larger, etc. With all these other excesses, I suppose it should then be no surprise that December would outdo all other months by having three official birthstones. Zircon, turquoise, and tanzanite are all recognized birthstones for the final month of the year. I guess we had better get started.
A long time ago, long before Canada was a nation, back in the early 16th century, a few energetic Scotsmen decided to slide stones on a frozen river at a fixed target as a form of competition. The sport of curling was born. After all one cannot golf in the winter! Who knew that the game would become such a favorite halfway around the world some 400 years later.
In mid-September, Bill Lesniak and I ventured a couple states west and south on a Buffalo Geological Society four-day fossil trip led by Jerry Bastedo. Our first quarry stop on a pleasant sunny Friday morning was in southeast Indiana at the Napoleon Quarry in Ripley County. It was a great site, but for me it might have been all that much better had I done a little research before the trip. But better late than never and here is what I have since learned.
Wayne County Gem and Mineral Club’s September Adirondack field trip was another great success. Seven spots in 4 days with the Saturday AM visit to Benson Mines in Star Lake attracting the most collectors. 33 folks convened and enjoyed a morning collecting in the dumps of the open-pit iron mine just outside town. Five of the other sites visited were repeats for the club (Rose Road, Benson Mines, Talcville, Valentine Mine, Fine roadcut, and Moose River). However, we had never been to the Seavey Road marble quarry north of Gouverneur. Thanks to Ken St. John, who had visited earlier with a small group of fluorescent mineral collectors, and to quarry owner Kevin Dibble, we were able to spend three hours in the large, and very white, quarry. As a new site for us, the Seavey Road location deserves a review.
October is another month with two official birthstones. If you are partial to wondrously terminated hard crystalline faceted gemstones, perhaps tourmaline would be your preferred choice. But, if you like the rainbow play of colors offered by opal, then stones cut to display the remarkable lustrous character of precious opal may touch your fancy. Since I’ve already written about tourmaline, let’s focus on opal in this birthstone review.
I have trouble finding one lone whole trilobite when I go out collecting in the Devonian of New York. And then along comes this note from central Poland where researcher Blazej Blazejowski reports that the eyeless trilobite Trimerocephalus chopini can be found preserved in trains with head to tail (or in trilobite lingo with cephalon to pygidium). He infers that the queues actually represent migratory chains as the ancient arthropods marched across the seafloor, perhaps in an unsuccessful effort to escape near and present danger.
Wouldn’t it be neat to find a queue of arthropods after splitting some Hamilton Group shales? Or maybe there was no reason for New York trilobites to migrate? Perhaps life was just too good to move?
Blazejowski, B., et. al., 2016 Ancient animal migration: a case study of eyeless dimorphic Devonian trilobites from Poland, Palaeontology, V. 59, p. 743-751.
So how would you like to wake up one morning and wonder how such a big rock got into your garden?
Where should I start? The 10 day August trip to Thunder Bay and back again was a blast. We all returned with enough minerals and memories to last through the winter (or at least until our trip to the Adirondacks in September!).
But first and foremost: Just as the 1959 stamp Issue in the header was a joint issue of the USA and Canada, this trip was a two country trip with WCGMC and the Niagara Peninsula Geological Society (NPGS) of St. Catharine’s, Ontario. Those of us from WCGMC thank NPGS for allowing us to join them, and in particular to their field trip leader Ashley Pollock, who planned the itinerary and set up the many visits requiring permission and outside leadership.
People come in all sizes and so do collectible rocks and minerals. There are collectors who prefer garden rocks, as big as they can carry (or even bigger). These people will do this until their yards or patios are completely covered by rocks. And then they start building piles. You know who you are! There are folks who like cabinet specimens of several inches. You need space to display these also and typically quality cabinet specimen can deplete the wallet all too quickly.
Me, I prefer mineral specimens that are called miniatures, no longer than 2” in their longest dimension. A few dozen can fit on a display shelf or in a drawer. Of course there are thumbnail collectors who specialize in specimens that can fit into a one inch cube. They even have neat little special boxes, called Perky boxes named after the collector/dealer that popularized the theme. And then there are the micromounters. These collectors can purchase much of their material less expensively and the number of available minerals seems endless, but then they require binocular microscopes and perhaps close-up camera lens to best view their prized possession.
But what about collecting minerals on thin section. Is there a place for that? OK, first off what is a thin section? According to the bible of the internet, Wikipedia tells us that a thin section is a “laboratory preparation of a rock, mineral, soil, bone, or even metal for use with a polarizing microscope”. Fine, but what is it? Let me try: a thin section is a tiny sliver of rock, typically mounted/glued onto a microscope slide that permits light to pass through all the transparent mineral phases. As it turns out if you mount a polished rock surface onto a glass microscope slide and grind/polish the surface down to 30 microns in thickness (that’s about 1/800th of an inch for the metrically challenged) then many minerals will display characteristic colors and properties upon the transmission of polarized light. In this way minerals can be identified under the microscope. Further-more their textures and how they are intergrown with each other can be used to interpret how the minerals grew and how a rock might have formed.
I have written about Green’s Landing east of Canandaigua Lake after each of my summer visits the past 4 years. This time I will keep the words to a minimum and illustrate a wonderful joint trip with mostly pictures.
July was a busy month for Bill Lesniak and his travelling rock and mineral kit stand. If you have not seen his operation, Bill sets up at whatever event will allow him and, on the behalf of Wayne County Gem and Mineral Club, offers free rock and mineral kits to youngsters. They do have to earn them though. They must cut out labels, display dexterity with glue sticks to apply them to the egg cartons he provides and then, with help, locate the 12 specimens (this summer: 6 rocks, 4 minerals and 2 fossils). In the end they go home with something that looks like this:
Published in the August WCGMC newsletter
Olivine is one the most common rock-forming silicate minerals on our glorious planet. It is found in iron and magnesium rich igneous rocks, both extrusive rocks like basalt (think Hawaii) and intrusive equivalents like gabbro and deep mantle rocks called peridotite.. When it is found transparent and unfractured, olivine can be faceted into a brilliant green gemstone. We call that gemstone peridot and it is the August birthstone.
Olivine Group minerals are nesosilicates, meaning that their mineral lattice consists of isolated silica tetrahedral that are connected by interstitial cations (most commonly iron and magnesium). This leads to the formula (Mg, Fe)2SiO4. End member Mg-bearing olivine is the mineral forsterite, while Fe-dominated olivine is the mineral fayalite. The term chrysolite is sometimes used to label intermediate composition olivine. Most olivine contains both magnesium and iron, but Mg-rich forsterite is more common than fayalite.
This summer was an Olympic Summer and I am sure many of you watched Michael Phelps or Simone Biles or others compete in Rio de Janeiro. For those who collect topical postage stamps, an Olympic year also brings a plethora of new stamps. Rochester Philatelic Association member Carl Miller is an Olympics stamps enthusiast, but his philatelic interest is a specialty within the overall theme of the event. Carl collects Olympic themed stamps that commemorate and depict Pierre de Coubertin, the founder of the modern Olympics. Continue reading
Many thanks to Stephen Mayer for writing this collecting trip note for the August WCGMC newsletter and also for allowing me to post it my blog.
By Stephen Mayer
Tammy and I are back from a vacation in the desert southwest. Naturally, we took some time between visits to National Parks to do a little fossil and mineral collecting in Utah. The setting and geology are quite different than in western New York.
Very thick shale and calcareous mudstones are widespread in Millard County, west-central Utah and contain some of the best Cambrian biotas in the world. Not only are there 505-520 million year old fossils abundant, but also recent volcanism in the same region has left its mark with abundant rocks and minerals. Specifically, well preserved trilobites and beautiful topaz crystals can be collected.
Published in the July WCGMC Newsletter
Admittedly, some of the Wayne County Gem and Mineral Club collecting trips are out of this world. However, that’s figurative speech as we have not yet actually figured out how to visit any true planetary bodies. No, Cobalt, Ontario does not count, not even Sudbury. But suppose we could travel to another planet to collect. What might we find? Let’s consider Mercury for starters.