The Tan Tan no Mi is a Paramecia Devil Fruit that was consumed by Dravolos Ashraf following his father's death. It enables the wielder to forge weapons from pre-existing materials, leading them to be a Forge Human.
The fruit itself was circular, last Ashraf remembered. Besides being circular, it was also silver in coloration with the letter "W" imprinted all across the fruit in white, thus making it difficult to see for the naked eye. The stem of the fruit appeared almost sword-like in its shape.