Malachite Triangles. The distinctive green of the mineral Malachite is the result of its copper content. The mineral was mined near Suez for its copper over six thousand years ago, and presumably it was played around with as an ornamental stone a long time before the usefulness of its copper content was realized.
The Urals of Russia was a major source of Malachite in the last couple of centuries; Christopher W. saw in the late 1960s, in the Paris apartment of a Russian emigree, a coffee table top of spectacularly striated Malachite at least 3cms thick.
Malachite is one of those gemstones attributed with protective capacity. The Ancient Egyptians envisioned a “Field of Malachite” as part of their lore associated with the afterlife, where all would be as on Earth but without suffering.