Your zodiac sign has a stone. Not the calendar-month birthstone on the gift-shop chart — the one astrology handed your sign long before modern jew...
Key Takeaway
Ruby is the red variety of corundum — the same mineral as sapphire — colored by chromium and ranking 9 on the hardness scale, second ...
Key Takeaway
Amethyst is purple quartz, and its name comes from the Greek for "not drunk" — the Greeks believed it guarded against intoxication. F...