Hammered Niobium RingsEngineered for a lifetime. Niobium is a durable grey silver metal which is NOT an alloy it has it's own spot on the Periodic Table so it's perfect for people who react to various other metals, as it's extremely unlikely you have a niobium allergy. Hand hammered to create a subtle but definite texture, reflective without being polished, this is the sort of ring that will probably provoke envious questions Note that any blue coloration in the pictures