First let's select our type
Is your gem plain color?
Is it transparent or opaque?
Is it two color or no color?
Gems all transparent colored gems such as ruby, sapphire, garnet etc. also including color change gems.
Multi-color and transparent(topaz, ametrine, watermelon etc)
No color and transparent(diamond, sapphire etc,).
Non-transparent (jade, opals, stars, pearls etc).