in case your wondering keep in mind the quartz crystal has 6 sides and on terminated one 6 termination facets at different angles. those are the growth plains, corundum has 3, topaz has one, and as you know you cant polish topaz with a facet right in the growth plain. the quarts can give you a bit of problems when on a growth plain angle too. its to do with the latus structure of the growth plains.