Rockwerks Lapidary Forum

Help,,,
I have cut a slice off of a 60mm sphere of tiger eye to make a cab.
However, the more I sand (320 grit on plate glass) the blacker it gets.

Hmmmmm, Im actually not sure on this one Paul. Will have to wait for someone else to chime in.

Hi Paul,
First are you sure it's real Tiger Eye?
Next thing if it is TE is the orientation of the flash. It should have been sliced at the 90° point from the brightest flash.
Other than that I'm not sure, I'll keep thinking,
Dan

Thanks, I'm sure it is TE. The black seems to be only on the surface, but I can't get below it. I thought perhaps it was heat from the cut, but one of the dark vanes split off from a nice golden part. no matter which of these two parts I sand I get a blackening on the surface. I have tried 2 or 3 different ways to overcome this. I used a diamond bit with a water drip. a diamond disc on a slow speed dremel, 320 grit sandpaper, and I even took it out back and rubbed it on the concrete patio. The finer the grit the darker the black. Perhaps I could get a pic up in a day or two.

A picture would help. If it's dark brown, it sounds like burning, but I never had Tiger Eye burn. If it's actually black, I have no idea unless the grit is breaking down and penetrating the rock fibers.

But if it does it on concrete, it's not the grit.

If its yellow Tiger eye and you overheat it it will turn red. Red Tiger eye comes from nature heating yellow or from people like us heating it. If its not oriented correctly the bands will look very dark, almost black. Grit shouldn't embed so much that it would change the color of the material.
Bob