They show a listing for 1/8" TiO2 pieces. I would call and ask them about purity.
john
Just FYI, Titanite (aka sphene) is CaTiSiO5. TiO2 is rutile, anatase, or brookite, depending on structure.
On that subject, MTI (www.mtixtl.com) sells synthetic rutile that so far is a pretty promising Zr-in-rutile blank. I'm going to be buying some more, as I want some solution ICP data to confirm the laser data I have, so if anyone wants to split a piece, feel free to ask.
Good thing I'm not a geologist then!
Actually I should know this because I used to find lots of sphene in my blueschist minerals. I simply forgot about the other name... Just FYI, I'm slowly entering all my blueschist minerals from California into the Condon collection here at UofO. At least it's a better home for them than my garage!
Well, I have no idea where Nick can locate a synthetic sphene. They're kind of a "garbage can" mineral from what I remember, with many unusual elements.
john