An yttrium-bearing silicate, often brown. It's a grounding stone associated with stability and Earth connection. (Note: IMA status/classification of 'Yftisite' has been complex; sometimes considered yttrian Titanite).
Brown, Yellowish-Brown, forms prismatic crystals
We do not currently have scientific information available for Yftisite Y now often classified under other names or as an yttrian titanite sphene.