Bone Donuts These Bone Donuts makes excellent pendants, earring drops or as links to make up a chain of donuts. You can even make a simple necklace all on it's own by simply tying the larger donut to a cord and putting it around your neck. The black bone donut is about 1 1/4 inches in diameter (32mm), making it a substantial piece that will set off any natural jewelry design. The smaller bone donut at the top is antiqued bone that has a 25mm outside diameter.