edit: my info was totally out of date. Ignore this post =\
Unless it was changed, I remember reading that perfect Gems are the highest that drop. That's Tier 5 out of 15 at 3 gems per tier meaning you need to transmute 59049 perfect gems to make one ultimate tier 15 gem which you will get after a couple of years and lose the next day due to some lag death :P. (sorry if my math fails but it is an awful lot of perfect gems anyway)
Do you guys think there is a point at which (in HC) it isn't worth it to continue transmuting gems into higher tiers because you start risking too much woirk for an absolutely tiny benefit? Or because 3 gems of a lower tier are arguably worth a lot more than the next higher gem?
Right now I'm transmuting Perfect gems into Radiant all the time.
I can see myself upgrading Radiants into Tier7 later on
Tier 7 > Tier 8? Big maybe for me....
Tier 8+? Unless for some reason I am absolutely swimming in gems I really don't see myself doing this.
Highest level that drops is 8, highest level gem is 14. 2187 level 8 gems if my math is correct. I'm not sure exactly how the progression works off the top of my head but I know that in the case of Amethysts you get diminishing returns (1% bonus at a time for a lot more work)
It isn't a question of "worth" in my opinion. You just gather the gems, then transmute if its possible or needed. For example if I'd transmute all my amethysts I'd get less vitality overall. By time we will all have many gems. If we can keep up our progress long enough there will be a lot more then actually will be needed by 3-4 characters. So the stash will hold most of them and that's nothing risky about that