Dutch Blue, Again

An old, obscure article I wrote on the subject of the pigment "Dutch Blue" and lapis lazuli has suddenly become relevant again, albeit in another obscure context. I discovered some discussion on the Ancient Japan Weblog about a frescoes in a tomb dated to the 7th or 8th Century. Researchers suddenly withdrew their assertion that the blue pigment in the tomb paintings were made from lapis lazuli. This retraction caused much puzzlement amongst scholars as no reason was given, and it appears that forensic analysis has not yet been performed. My article asserted that lapis was used as a pigment in the Edo era, but there is no evidence that it was used as early as the 7th or 8th century in Japan, so its use at such an early date would have been a significant historical discovery.
I won't repost the entire obscure discussion, but I will point towards the original post at the Ancient Japan Weblog and the followup discussion on their associated forum.