Large rutile quartz! It's about 20mm^_^ Combined with strawberry quartz (about 9mm) and crystal quartz (about 11mm)♡ Inner diameter is about 16cm. Size adjustments are possible, so feel free to comment^_^ Rutile quartz is all about fortune! I've combined it with strawberry quartz, which provides healing and restores smiles and confidence♡ Crystal quartz will cleanse and smooth the flow of energy.