[ATM] BVC material properties

[Mark Holm]

Tom Krajci wrote:
>> From: George Anderson <tillerman1 at videotron.ca>

>> The mirror blanks are made from layers of BVC that are fused together.

According to Andre, also on this list several years ago (as I recall),
the glass does not come from Pilkington in the BVC form.  He does indeed
fuse stacks of sheets together.  In the fusing process, he also uses the
heat to modify the glass micro structure, producing the BVC product from
a starting material that was glassy and (probably) transparent.  At
least one list member has attributed this transformation to
"devitrification", a phenomenon in which prolonged heating at the right
temperature causes crystals to precipitate in some glass compositions.

-- 
Mark Holm
mdholm at telerama.com