Hello, I am a student of gemology and just can't find a good explanation for the new "Glass Filling" treatment on Rubies, especially from Madagascar. The following is a short description of how the treatment is done; 1) Ruby rough is dipped in Hydrofluoric acid for about 48 hours. This creates some holes, like very precise drills on the gem which helps to increase the clarity too. 2) The gem is placed in a heating oven for about 5 to 10 hours with an average temperature of 1800C. 3) During the heating process, Silicon powder is added all through the gems, which are somehow part of the ruby when its cooled down. the silicon makes the very low quality rubies good for even jewelers thats why its becoming more & more popular everyday, although the treatment is not acceptable!!! This Ruby has a massive practical difference compared to classical heating... It cant undergo electrolysis. If it is passed through electrolysis the stone is somehow cracked from the surface which makes it useless for jewelery. Why should this cracking happen? Any Help will be highly appreciated.