Certified 4 mm round brilliant cut black Moissanite prong set in 925 Sterling silver with black rhodium and a double safety latch. Moissanite is certified and will test positive for a diamond. 📖What is Black Rhodium and what is its worth? Black rhodium is a proprietary alloy that combines white rhodium (a form of platinum) with other metals to create a signature dark gunmetal look. It’s a closely guarded commercial secret and takes significant time to procure causing the jewelry with it to be more alluring and more expensive.