look at https://wolcendb.erosson.org
which gem can give u what result for which item, dont suggest those 9 possibilities, every item can have other results

I find it very confusing. Based on the crafting description, I would expect one of the 9 possibilities under Eternal Diamond. The game does not show you a long list of Eternal crafting possibilities (like +Elemental damage in Rings). Even that, I still got a +Fire spell damage with a socketed gem. How do I get Fire damage with Eternal? It should be Frost.

hmm it may be broken, should work erieban tear, when ure adding a new affix/suffix
ive burned a lot of mats right now and results seems to be random on the amulet, however i dont use it normally, so make some tests yourself, but i bet it requires fixing

however tried it with eternal lapis azuli with steel ring and results seems fine, so hard to say, u need to wait for hardcore crafters opinions, i have usually not a lot of mats, as i dont buy them and not duping, so i dont craft so much

The gems increase the chance of crafting 1 out of a few particular affixes associated with the gem, but they do not guarantee them. You might still get an affix that is not associated with the gem you used.

so translation needs to be corected