The archive
Step-by-step identification guides for the rocks and minerals people find — and most often mistake for something else.
Field Guide
New to rock collecting? Here's the beginner's field kit, the laws about where you can legally collect, the etiquette that keeps sites open, and the easy-to-find rocks that make a great first haul.
3 min read
Crystals
Crystals are identified by their shape, symmetry, and physical properties — not their color. Learn the seven crystal systems, the habit vocabulary collectors use, and the quick tests that separate real crystals from glass and dyed fakes.
3 min read
Minerals
Minerals are identified by a short checklist of physical properties — hardness, streak, luster, color, cleavage, crystal form, and a few special tests. Learn to run all seven and narrow any specimen to a name.
3 min read
Methods
Hardness is the single most useful clue for identifying a rock or mineral. Learn the Mohs scale from talc to diamond and how to test it with a fingernail, a coin, and a steel knife — no lab required.
3 min read
Minerals
Is that beach pebble an agate? Learn the flashlight translucency test, how to read agate banding, and how to tell agate from jasper, chert, and plain chalcedony.
4 min read
Minerals
Gold and pyrite have fooled prospectors for centuries. Learn the streak, hardness, shape, and sun tests that separate real gold from fool's gold in minutes — no chemicals required.
3 min read
Field Guide
Geodes hide crystal-lined cavities inside plain round rocks. Learn the weight test, the sound test, and the surface clues that reveal a geode — plus the right way to open one.
3 min read
Look-alikes
That glossy black 'obsidian' from a beach or backyard is often furnace slag. Here's how to tell natural volcanic glass from man-made glass using bubbles, color, location, and fracture.
3 min read
Minerals
Quartz is the mineral you've already found. Learn to confirm it with the glass-scratch test, spot its six-sided crystals, and name its varieties — amethyst, rose, smoky, and milky quartz.
3 min read
Meteorites
Learn how to identify a real meteorite — fusion crust, regmaglypts, the magnet test, and density — and how to rule out slag, hematite, and magnetite, the three most common impostors.
4 min read
Field Guide
A step-by-step method for identifying rocks and minerals at home using the streak test, Mohs hardness scale, luster, and density — no lab equipment required.
5 min read