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: 7492
- Availability: 20
- $10.63
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$8.50