A quartz crystal included by hairy (tremolite?) and cookeite spheres.  It is nice that the quartz crystal has good luster and transparency, so the inclusions can be fully appreciated.

It seems that the first generation (which now constitutes the internal phantom) was included heavily with tremolite.  Cookeite spheres deposited on its surface, and then a second generation of quartz grew over all that, creating what you see here.

A beautiful and unusual example of rare Japanese material.