Tungsten alloy sphere. 2.75" diameter, 3kg. High density. Suprisingly heavy. Great conversation piece. Includes certificate of chemical composition and interesting tungsten facts. Machined from aerospace grade tungsten, this sphere is an excellent contemporary addition for your desk at work or side table at home. Surprise your colleagues and friends with the sphere's density, weighing 3 kilograms, yet fitting into the palm of your hand. Tungsten is one of the densest naturally occurring elements, and now you can add one of nature's wonders to your own collection. If you like the sphere, don't forget to check out our Tungsten Cube.