I was looking for a way to craft soulgems, but was often unsatisfied with the couple of implementations you may find around - I disliked the Smelter and Forge workbenches alternative since they mess with immersion and smithing experience respectively. Then I found an Oldrim mod that used the Atronach Forge quite interestingly and I loved it, but since I just don't know how to port them to Special Edition (let alone temper with scripts), I decided to make my own without messing with vanilla scripts or adding to them, thus this is a script free mod that relies on vanilla items only.

The recipe pattern reasoning behind is mimicing the complexity of the original Atronach Forge Recipes and about increasing a soulgem's size with inferior soulgems plus a precious gem/jewel that contains such precious gem.

Installation.
-Use your favorite mod manager and load the .esp file.

How to use?
-Just as you would use the Atronach Forge - Go to the Midden, drop the items on the Offering Box and pull the lever. No sigil stone required.

-Recipes-
Soulgem Fragment  = 1x Glass + 1x Bone Meal.

Petty Soulgem = 1x Soulgem Fragment + 1x Garnet || Flawless Garnet || Silver Garnet Ring || Silver Jeweled Necklace.

Lesser Soulgem = 1x Soulgem Fragment + 1x Petty Soulgem + 1x Amethyst || Flawless Amethyst || Silver Amethyst Ring || Gold Jeweled Necklace.

Common Soulgem = 1x Petty Soulgem + 1x Lesser Soulgem + 1x Ruby || Flawless Ruby || Silver Ruby Ring || Gold Ruby Necklace || Copper and Ruby Circlet || Gold and Ruby Circlet

Greater Soulgem = 1x Lesser Soulgem + 1x Common Soulgem + 1x Sapphire || Flawless Sapphire || Gold Sapphire Ring || Silver Sapphire Necklace || Copper and Sapphire Circlet || Jade and Spphire Circlet || Silver and Sapphire Circlet

Grand Soulgem = 1x Common Soulgem + 1x Greater Soulgem + 1x Emerald || Flawless Emerald || Gold Emerald Ring || Silver Emerald Necklace || Gold and Emerald Circlet || Jade and Emerald Circlet

Black Soulgem = 1x Grand Soulgem + 1x Human Heart

Notes:
1. You can use either empty or filled version the of soulgem on recipes that requires them.
2. "||" means "or", you can use the simple precious gem or a listed jewelry item that has such precious gem.

Extras:
-I added some Mill recipes to obtain Bone Meal, go to any functional Mill:

x2 Bone Meal = 1x Human Skull
x4 Bone Meal = 1x Troll Skull
x8 Bone Meal = 1x Dragon Bone

-I edited the Miscelaneus Vendor Leveled List and they now may sell Soulgem Fragments, so if you want that feature you may need to Bashed Patch if you've another mod that edits such list, or just load this .esp prior to your mods so they can overwrite it.

Limitations.
1. As much as I'd love to implement it, atronach forging cannot craft in bulk without scripting. However:
2. Adding double ingredients of each will not result in 2 soulgems, but you can place a combination of, say 10 glass and 10 Bone Meal and just spam the lever button - the Atronach Forge will just consume a single unit of each ingredient.
3. Recipes can only receive 1 unit of each ingredient (as far as I could see, I just found no way without scripting).
4. Because of how the atronach forge identifies what should it create with a given recipe, there can only be 1 recipe for each item, thus there can't be an alternative recipe for each soulgem.



Disclaimer.
This is my first mod ever - I am not very good in regards of balancing, feel free to drop your suggestions on how making the recipces more immersive, balanced, or whatnot. I may add other fun atronach recipes and other utility recipes such as creating Powdered Mammoth Tusk in the mill with Mammoth Tusks, etc.

Thank you.