Grading & Types No topics

Type I (elite), Type II (Petrovsky), Type III, Type IV.

Type I (elite), Type II (Petrovsky), Type III, Type IV.

Subject	Replies / Views	Last Post
Petrovsky Shungite: the rare, almost-unknown variety named after Peter the Great Category: Grading & Types Topic started 1 month 18 hours ago, by Research Last Post 1 month 18 hours ago by Research	Replies:0 Views:78	Last Post by Research 1 month 18 hours ago
Why your vendor matters: properties vary by mine layer (Kovalevski / Rozhkova) Category: Grading & Types Topic started 1 month 2 days ago, by Research Last Post 1 month 2 days ago by Research	Replies:0 Views:29	Last Post by Research 1 month 2 days ago