Blast (Diamond) and Shock (Topaz) are easiest to get big gem hotspots on, with diamonds you’ll find good coal at the elevation you find it and topaz can have fossil in with it at the right elevations, but all of what you’re looking for will be there if you use a build like this though you may have to change elevations when mining. Most critical pick is Olympus alone at lv. 8 (so you will want a T6 so you can take it, that gives more gem seams anyways), that will give you big hotspots on it’s own-
World “Builds” thread - Creations / Sovereign - Boundless Community (playboundless.com)
I just rolled a similar Shock to this build (Farewell, off Alcyon, portal at Paka’s Palace) that has 747k topaz, there were a few switches but the best spots mostly came from biomes in this build.