The crafting-recipe for Diamond Chairs has to be unlocked first by taking/crafting an Iron Chair for the first time (which is unlocked by taking/crafting an Obsidian Chair). To craft 1 Diamond Chair, you'll need (as of R26 in December 2015): * 4 Diamond Rods made of Diamond (bars) in a Processor * 2 Diamond Slabs made of Diamond (bars) in a Processor * 1 Glob of Goo made from Mold in a Processor or looted/harvested from many creatures including Pigsies Crafting/taking a Diamond Chair for the first time will unlock the crafting-recipe for Lumite Chairs.