I am back from the rock show! I drove for several hours through some pretty heavy thunderstorms to attend this one, and came home with my smallest haul ever. Still, I'm very happy with these pieces!
First up, kammererite! This sparkly purple mineral is a chromium-bearing variety of clinochlore. This piece came from Turkey.
While this mineral can form wafer thin, mica-like crystals like other clinochlores, this piece features fantastically well-formed spiky octahedrons. What nice crystals!
Kammererite's color is idiochromatic, meaning the color is an inherent part of its molecular structure! (The vast majority of minerals are allochromatic - naturally colorless stones that get their colors from inclusions and impurities.)
Gobi agate, from Mongolia! Agates in the Gobi Desert get naturally polished by wind and sand, wearing away some parts of the banding and leaving others standing out as ridges. Usually these ridged bands form circular eye-like patterns, but this guy's a weird one! Super wrinkly-looking specimens like this are sometimes called "tendon agate." Hey, with that shape and those wrinkles, doesn't he look a bit like... no, I shan't say.
Another jasper for my collection! Anyone who's been following my blog a while will recall that I have been obsessed with collecting "fine jaspers" recently - the porcelain-textured, extremely fine-grained jaspers which can make "egg" formations. This material from the Black Sea in Turkey is a fairly new find, and might just be one of those! No eggs here, but even in this unpolished piece we can see the distinctive streaks and clear color boundaries that mark nodules of fine jasper. I'm totally adding it to my jasper shelf.
Here are a rough specimen and a polished specimen of shattuckite! The rough specimen features a thin layer of shattuckite growing both on and inside of a quartz crystal! The polished piece has polka dots of deep blue azurite!
With the distinct tealy blue of a copper mineral, this stuff can often be found hanging out with its cousins, malachite, azurite, and chrysocolla. However, shattuckite is much rarer than those minerals! Both of these pieces came from a mine in Namibia.
Here is my new Most Valuable Mineral, and the reason I only came home with a few rocks this year. I blew the whole budget on Her. This super uncommon mineral is a huuuuge crystal of sapphirine! (Like seriously, most sapphirine on the market are dinky little thumbnail specimens; this thing is massive.)
The name sapphirine means "resembling sapphire," but the two gemstones aren't related. Sapphirine is a magnesium aluminum silicate, and is a metamorphic rock that forms under intense heat deep in Earth's crust. Cut and faceted pieces of it exhibit STRONG pleochroism, meaning they change color depending on the viewing angle. However, you'll seldom see it faceted because it's rare enough to be pretty much unknown as a gemstone, and only of interest to mineral collectors.
This big crystal was mined in Madagascar, from a deposit discovered in 2023! Crystals from this locale set the new best-of-species standard for sapphirine. How cool is it that we're still discovering new mineral locales?
