Bottom left: Cost scaling more precisely for relevant Tiers.

Top right: Same but empowered stops at Tier 77.Top center: Required amount of runs / gold / time (time is a rough approximation for 3-5 weeks into the season) to get a gem to 90 with all empowered rifts.Top left: Cost for empowering (basically +1 gemup).If you want to see the numbers, here's my Excel sheet (explanation see below): I assumed ~3.5 months and 200b/h early game, increasing up to 1000b/h near the end of season. Keep in mind we know neither the exact duration of this season nor the exact XP/h values that people will achieve. I calculated numbers for P1400 / Tier 90 gems with my solo Natalya setup(dual wield, no mainstat on jewelry, full diamonds, nonancient amulet), which will be pretty early in the season but for casuals like me it will still be decently high. It's about when to upgrade which gems and how to use our gold optimally. Here's some math on Caldesann's Despair I did a while ago and I decided to share it now.

Diablo 3 what is caldesann's despair