Rotten Stone= Talcum Power?

[joez]

I have some rotten stone (power) at home, and I was wondering if anyone can tell me if it is just another name for talcum power?

Thanks
Joe

[Eastie]

Rottenstone (or Tripoli – from where it’s said to have originated) is a little different to talc, however both are naturally occurring silica. From what I can remember it’s something like this:

Tripoli: (Microcrystalline) Silicon Dioxide
Talc: Magnesium Silicate Hydroxide

I have a feeling I may be wrong though?

[joez]

Thanks for your help.

Does that mean I can use it in Shellac as a base coat/ grain filler? Or should I just go out an order some Talc?

[Eastie]

I'd opt to stick to the guidelines in the polishers handbook and go with talc for creating a grain filler/sanding sealer.

Tripoli is used during french polishing and as a cutting/rubbing compound to rub out a finish. I've a feeling the crystal structure of tripoli is a little different to talc (talc is softer and breaks up by 'flaking' into very thin layers). When it comes time to lightly sand back the grain filler/sealer the talc will leave a silky smooth finish - I'm not so sure tripoli will do the same. Being different in size/structure tripoli may also cloud the grain.

Most art suppliers stock talc, but for the good stuff click here:http://www.ubeaut.com.au/talc.html

[colh]

I understand that Tripoli powder is the abrasive component of UBeaut's EEE polishing wax. My guess is that it might be more abrasive than talc.

for what its worth

Colin