Lapidaryforum.net

Rock Art => Cabochons, Intarsias, Cameos => Topic started by: Felicia on January 27, 2020, 01:06:54 PM

Title: Slab
Post by: Felicia on January 27, 2020, 01:06:54 PM

Was looking through old listings (I'm new to this site) and saw a cab of "large wave hill dolomite". I bought a large slab of that a couple of years ago, now know what is, but where is large wave hill? Second thing- just made a set of small sugilite cabochons for earrings, pendant, and ring. Got nice polish, but not glassy. Is this normal for sugilite? My first time using it. Beautiful purple, slightly translucent.

Title: Re: Slab
Post by: lithicbeads on January 27, 2020, 04:11:33 PM

Yes it is normal. sugilite is a mix of different hardnesses for the most part. Wave hill is in Australia. That limestone takes a killer polish.

Title: Re: Slab
Post by: Felicia on January 27, 2020, 06:02:50 PM

Thanks. Have done many things over the decades but not that one till now. All this posting is done on my phone, am trying to send photos.

Title: Re: Slab
Post by: gemfeller on January 27, 2020, 10:09:58 PM

I cut a fair amount of sugilite and it can take a very high polish.  But it isn't necessarily easy.  It resists standard diamond polishing and most oxides. After lots of trial and error my solution is an oxide mix I'm told is no longer made called Holy Cow!  I only have an ounce or so left and can't get more.  Perhaps someone here can suggest a similar polish - I've heard there are such things but can't recall the names.

I use just enough polish to lightly moisten a leather lap and use firm pressure, repeating frequently so as not to overheat the stone.  My method requires 3 or 4 applications of small amounts of polish to bring the stone up to the polish level I like. 

Here's a recent example:
 [ You are not allowed to view attachments ]  

Title: Re: Slab
Post by: Felicia on January 28, 2020, 11:28:55 AM

Thanks. The diamond has given a quite good polish, better than cerium. Don't have any chrome oxide, I hate the stuff. (Too messy, not  enough improvement.) If it's a mix of oxides, maybe cerium and tin, will have to try it sometime. Will need another lap.

Title: Re: Slab
Post by: southerly on February 11, 2020, 01:21:15 AM

Sugilte varies greatly in quality, some it is really hard and takes a superb polish and some is almost chalky and porous, most is in between.

Wave Hill dolomite comes form Mexico.

There is a Wave Hill Station is Australia that is well know for fossicking, is part of a large igneous complex and is best known for gem quality prehnite and dark purple amethyst. There is also agates, quartz and hematite.

David

Title: Re: Slab
Post by: Felicia on February 11, 2020, 08:12:41 AM

Thanks, good to know. Unlikely to get to Australia, although it would be nice.

Title: Re: Slab
Post by: victor1941 on March 06, 2020, 08:16:53 AM

Dose anyone know if wave dolomite polishes well in a vibe tumbler?