the new gemetrat treatment is very stable–does not discolor
with age, does not shrink and is therefore very mcu better than
oils (which can discolor or dry out) and opticon (which can
discolor and shrink) Depending upon how opticon is used there
is another problem. A method used by most soaks the stone in
the first material while heated and under vacumn, alowing for
great penetration. The stone is then dipped in the hardner.
The problem is that only the surface is hardened. The inner
material is still liquid and subject to a greater amount of
expansion if gently heated, in some cases causing the stone to
break. Gemetrat is solid through-out, doesn’t discolor or
shrink. Al Gilbertson