Rock Lab
Become a rock scientist 🔬
Real geology, made for kids — straight from a mining engineer. Learn how gems form, what makes them special, and how to take care of your finds.
Rock of the Week
Labradorite
Tilt it in the light and watch it flash electric blue!
Bria's Pick
Amethyst Geode Half
My favorite — a whole secret crystal cave you can hold.
Big rock questions
What is a mineral?
A mineral is a natural solid where the tiny atoms are lined up in a repeating pattern. Rocks are made of one or more minerals stuck together. Every gem you find is a real mineral the Earth grew!
Why do crystals grow in shapes?
Atoms stack in the exact same pattern over and over, like tiny building blocks. That's why crystals grow flat faces, straight edges, and sharp points instead of just blobs.
What does hardness mean?
Hardness is how hard it is to scratch a mineral. Scientists use the Mohs scale from 1 (super soft) to 10 (super hard). Most quartz gems are a 7 — harder than a steel knife!
How do gems form?
Deep underground, hot liquids and melted rock cool down very slowly. As they cool, atoms join up and grow into crystals — sometimes over millions of years. Slow and steady makes the best gems.
What is a geode?
A geode is a hollow rock with a secret garden of crystals grown inside it. From the outside it looks like a boring lumpy ball — until you see what's hiding within!
Why does labradorite flash?
Light sneaks between super-thin layers inside the stone and splits into colors, like a soap bubble. That magic blue-green flash even has a fancy science name: labradorescence.
The Mohs Hardness Scale
From softest (1) to hardest (10). A mineral can scratch anything softer than itself. Most Kid Diggins gems are a 7!
1
Talc
2
Gypsum
3
Calcite
4
Fluorite
5
Apatite
6
Feldspar
7
Quartz
8
Topaz
9
Corundum
10
Diamond
How to clean your find (safely!)
- 💦 Rinse it under cool water.
- 🧽 Wipe gently with a soft cloth.
- 🚫 Water only — no soap, no tools, no scrubbing.
- 🧑 Always ask a grown-up first, and never put rocks in your mouth.