So, I went for broke. Initially I was shocked at how baaaad it looked.
0.66% amethyst…
5.5% bitter beans.
Then, I explored it
15mins of mining yielded 2ss of amethyst
Guess rules are different on large planets
Oh…2ss of beans in about 35mins too
Still have 49 regions to look at lol
Definitely didn’t get quite what I anticipated but its still going to yield some nice materials.
I did also mine at around 11 alt. Plenty of gold and good amounts of fossils too
Nice!! 
On bitter beans, I’d absolutely take one large maze area over a planet with a much higher count where it is scattered and on other biomes. Maze is just SO much easier to collect on, good roadrunner/hopper hunting biome too. I’ve got a few I can just bounce around now when wanting to collect, very quick easy coin there!
Next roll I’ll try testing some different land biomes… lv. 8 is the tricky one on Corrosive, none of them are good for amethyst/emerald, just a matter of getting the least harmful from what I’ve experienced. Though if you take both Gleam Lake at lv 4 and Floating Shrapnel at lv 8 you can pretty well light up the planet like a Christmas tree from the merges in places. 
Well it’s all about the amount per chunk to me. The percentages are really misleading if you ask me in game when it populates on boundlessinfo it just seems like better info. 5.5% in game I bet is a lot better on boundless info.
Ok, this worked better than I think any I’ve done since Proserpina, though I think still lower than that one - planet Hethi open now off Norkyna. 
Might open a TNT portal later to it near my other one.
… However, I think this can be improved on. Still had a LOT of open ocean - so lots of emerald, but I’m not aiming for that. This calls for another experiment. 
The general idea of a lot of small land areas to get more shoreline and shallow water does look to be good. 
But I might need more. And Ocean might need to go, I had put that back in for this.
Hmm. Well, if next test works better I’ll post! 
I got a halfway-decent amethyst world (temporarily labelled “Scrunchions” 'cos I was hungry at the time) where the best spots seem to be where Towers of Hanoi meet Clam Ocean, which was the only ocean biome I had. but it could be coincidence. Is someone (@bucfanpaka) keeping a spreadsheet of every biome combination to see what gives the best yields? My time for proper sciencing is very limited but it would be useful.
I should keep better track. Admittedly I often roll just to distract myself - too mentally fried to keep good records lately like I was doing when I first started this thread. 
But making general mental notes on what works well for different types of builds. I didn’t write down the ones for the one I just put in for but if it turns out really well, I can go over the form and probably remember most. 
For the record, my Scrunchions picks were these.
I chose Overhanging Cliffs and Tentacle Outcrop purely for aesthetics and Gleam Spiral for hunting because I do more than mine but the rest were aimed at maximizing shallow water without vast landless expanses. I would probably choose Gleam Lake next time because it gave me (relatively) good Amethyst on a previous Toxic roll but I was experimenting with this one.
Nice! Got some of those on the one that I’m waiting to pop, though I did Gleam Rain for 8 on this one, Tentacle Outcrop IS a really cool looking biome.
… Latest, Nal V, up off Alcyon, probably open a portal at some point. But, though it does look at first few regions like there could be some good spots, lower count than the last. Still a good bit of deep water. Might wait to experiment again, losing track of what I’ve got and several not fully mapped so probably should just play with them for a bit. 
Ok Paka-chan I don’t know what caves to pick what caves do I pick for everything @bucfanpaka
Yep, I’ve found standard caves to be the safest for mining - there are other types (I forget which, brain not awake yet 
) that are good for harvesting combustion particles and all, but on the mining side I haven’t liked others I’ve tried. Like, Small Caves creates a LOT of them, bunch of lava traps.
However, someone who has played more with the cave choices might have better input here.
If my name was Chan, would you call me Chan-Chan?
Wait, what if my name was Chan-Chan… ? …
Regards,
Are you by any chance Japanese cookie monster
I usually throw something like Huge Crooked Caves for L8 I don’t expect to mine a lot of resources under (eg. on a Corrosion word), just to make it more interesting. I stay away from those caves that open to the surface a lot because of some bad (“Three elite elemental spitters! Run away! Oh sh----” … “You have been defeated. Return here or go home?”) experiences. Other than that, yeah, Standard Caves and maybe the occasional Large Simple Caves.
Large flat caves can do one of two things:
totally destroy the biomes gem spawn area if RNG puts it in the wrong spot. I’ve found floating mountains will do the same with sapphire. For amethyst I’ve had one work great that kept all the lava out the way and another push the lava down to cover 6 to 11 alt, resulting in a 0.03% roll lol.
The good roll gave me a 20x10 or so area another 40x30 and a smaller 8x4 jammed full of easily accessible amethyst with zero laval.
Does RNGesus like you…
Does anyone have suggested biomes for creating a T6 Topaz world? I saw @ghandymarshall mention they had mastered the topaz world but I have not been able to find any info on what biomes to choose. I have two planets ready to go!
This thread is so helpful! I used info from this thread yesterday and ended up creating a planet (Heliotrope) that ranks 2nd for Amethyst and 10th for Emerald!! I have another code and want to try for Topaz now HUGE thanks to everyone sharing their knowledge!
@bucfanpaka can help too I’m sure.
My chill planet Ulthar which I made for just Bitter Beans had a large amount of Topaz and Sapphire … and it was very concentrated in certain areas. It’s detailed here:
