Without over thinking it and simply answering the question, (the question didn't say based on those definitions) I'd say:
Peridot
Rhodochrosite
I guess one could argue a case for rhodolite, but, since it is a variety that is dependant upon a mix of 2 species even though the species may be idiochromatic, I'll dismiss it on a technical flaw.
The gemmological defenition is a mineral that is coloured by elements that are an essential part of the chemical composition.
That is a not so fortunate definition unless you specifiy the rules.
If you translate it from greek, idio + chromatic just means self-coloured. So that applies to everything.
Rhodolite for instance has iron in its chemical composition. The colouring agent in rhodolite is said to be chromium, making it allochromatic. But if the iron would not be present, I'm sure that would affect the colour.
The same goes for tsavorite. Manganese is present in the chem. comp., but the colour is attributed to vanadium and chromium. Manganese itself is also a colouring agent and without it, the colour would also be different.
Joined: Mon Oct 17, 2005 10:56 am Posts: 6461 Location: The frozen north prairie :-/
See what you started, Bill !
Okay, I'll give on the tsavorite, hesitantly, but according to GIA rhodolite garnet is colored by iron, part of its chemical composition, hence idiochromatic.
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