Natural obsidian test stones give precise readings when testing for gold purity. Obsidian is a volcanic glass produced when lava becomes cold. It is been used for years to make the sharpest knives. Obsidian test stones, on the contrary to rougher test stones, have a perfectly smooth surface that provides more consistent and reliable readings.
Transline - Natural Obsidian Test Stone
- Brand: Transline
- Product Code: 7494
- Availability: 2
- $18.95
-
$15.16