As far back as 5000 BCE, there are references to bloodstone’s healing ability. Babylonians used it especially for blood disorders, for protection, and for divination/prophecy. The Egyptians felt it increased strength, made them invisible, and helped defeat enemies. Others believed it could help with weather magic and legal justice.
I have to wonder when bloodstone became a birthstone for March; I certainly don’t remember it from when I was young–back in the Dark Ages ;-)–and it certainly seems to be a bit more…shall we say…intense? than many other birthstones. But hey, it gives a choice (perhaps men prefer it to the more feminine aquamarine?), and gives us a chance to learn more about a very useful stone.