Peridot.

Peridot is the gem-quality variety of olivine, a magnesium iron silicate that forms in the upper mantle and arrives at the surface inside basalt flows. The colour comes from iron in the crystal lattice rather than from any trace impurity, which is unusual and gives peridot one of the few naturally consistent colour ranges in gemmology. Most pieces sit somewhere between olive and lime green.

The historical source is the small island of Zabargad in the Red Sea, mined by Egyptian crews from at least the second millennium BCE. Pliny called it topazos, which is part of why the gem nomenclature got tangled until the nineteenth century. Hawaiian beach sands at Papakolea contain tumbled peridot grains weathered out of basalt, and the Pakistani Sapat valley deposit has produced larger clean stones since the 1990s.

In modern crystal practice peridot sits with the heart and solar plexus chakras. It carries a noticeably lighter mood than the other green stones in the range, and is the piece people pair with seasonal change, returning energy after illness, or the start of a new project. The hardness is modest, so a peridot ring suits occasional wear better than daily knock-about. A soft cloth and warm water keeps it bright. Avoid acidic cleaners and steam, both of which can etch or fracture the stone.