Contact
One person answers everything here, so replies are not instant.
LINE
Official account
The fastest channel. LINE is widely used in Taiwan, Japan and
Thailand; if you are elsewhere, use e-mail below.
What can be answered here
Questions about a method described in an article, corrections to something published here, and press or permission requests.
What cannot
No identification is issued from photographs, and no valuation is given by message. Where a stone needs a formal opinion, the correct step is a testing laboratory.