Double cut brilliant

I have a question about a square table on a 1/4 ct diamond.
When I first looked at it with a 10 loupe I thought it was a cz.
clear but every facet edge was scratched. Tested it with a
diamond checker and it was a diamond. When did they stop cutting
double cut brilliants. This was a very old ring. Any help
appreciated. R Goll Indep. Ks