THE JGRL GEM LIBRARY
Get to know gemstones.
Discover the reasons for their beauty.
The structure behind a color. The place a gem formed. The cut that brings out its light.
A collection of fundamentals to help you understand each stone.
Crystals / Origins / Colors / Hardness / Cuts
EXPLORE THE GEMSTONES
Explore gemstones
Search by name or color to discover a gemstone.
Opal
Opal
A hydrated silica gem. Moving flashes of color, known as play-of-color, are a celebrated characteristic of some varieties.
- Mohs hardness
- 5–6.5
- Crystal system
- Amorphous
Pearl
Pearl
A gem produced through biological processes. Properties vary with the mollusk and freshwater or saltwater environment.
- Mohs hardness
- 2.5–3
- Crystal system
- Layers of microcrystals and organic material
Illustrations suggest color and shape. Individual stones vary; each gem page includes further details and references.
A LITTLE KNOWLEDGE, A DEEPER APPRECIATION
The more you know,
the more there is to discover.
How do hardness and toughness differ?
Understand the language of gems, one idea at a time.