Agate
Blue agate is almost certainly dyed. Image by Robert Ramsay from Pixabay.
Article: Common Gemstone Treatments Cheat Sheet
Credit: Pixabay
Gemstone | Quartz, Chalcedony, Agate |
Treatments | Dyeing |
Natural or man made | Natural |
Gem State | Other |
Color | Blue |
Transparency | Translucent |