This top is made from aerospace-grade tungsten heavy alloy. Its delicate lines, graceful beauty, and perfect balance belie the surprising density of tungsten. Precision machining and a rigorous inspection process ensure that your top exceeds your expectations for this premium product. Spun by hand on a flat surface this top will easily spin for two or more minutes. We have spun it for over five minutes using other means. Tungsten is very high density and surprisingly heavy, especially when compared to other typical desk items or toys. Great conversation pieces. Certificate of chemical composition and interesting tungsten facts are available via an email to our contact form. This top is an excellent contemporary addition for your desk at work or side table at home. Surprise your colleagues and friends with the top's density, of 0.614 lbs/in3 (17g/cc). This top is 90% tungsten with Nickel-Iron for the remainder. 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 tops, don't forget to check out our Tungsten Cubes.