. Despite
what I heard about other mines producing green datolites, one of the Isle
Royale Mines seems to be only one I'm sure that produced "well-greened"
(no bluish tint) datolites due to the weathering of very minute copper
inclusions by ancient brines. The interesting thing about those datolites
from Isle Royale mine is that they're like sponges, soaking up water and
as a result, their colors intensified. The datolites from that mine may
be most greenish of any datolites found so far (those greenish datolites
from Centennial Mine tend to be more bluish). Most datolites from Isle
Royale are white and some came with black to gray copper inclusions.
Again, this mine dump had
been bulldozed several times and I don't know if any more datolites still
can be found (never have been there).
Looks bit more turquoise colored when wet.
Typical datolites with gray copper inclusions
Most greenish datolites(without bluish tint) I have seen so far.
