Glass Goblet

I was with a group of people and were were pouring wine into a glass goblet.  The goblet was a fancy glass made with lots of geometric designs in it.  We decided the goblet was too big and needed to be made smaller.  I decided to cut the goblet in half and take a slice out of the middle.  Somebody told me we couldn't cut it but I had a knife that would cut the glass.  Once I got the knife started it just cut right through the glass like slicing cheese.  The goblet was in half then and we had to join it back together.  The two side did not match up evenly so there were spaces in it.  I got some clamps out and clamped the glass together.  Then I took a torch and melted the glass together.  There were still cracks whee the glass was joined together.  We took pieces of window pane and melted it into the cracks.  I knew that would not work when the glass cooled down it would crack.  We decided to fill the cracks with silicone instead.