Imagine stirring your tea and having your spoon disappear into your tea… melting quickly away. When one of Professor Sir Martyn Poliakoff’s Periodic Videos viewers sent a metal alloy, Field’s Metal, to their office, Poliakoff asked senior technician Neil Barnes to create a metal alloy spoon that would melt in tea. Watch as they experiment with it in the video above.
Field’s metal, also known as Field’s alloy, is a fusible alloy that becomes liquid at approximately 62 °C (144 °F). It is named after its inventor, Simon Quellen Field. It is a eutectic alloy of bismuth, indium, and tin, with the following percentages by weight: 32.5% Bi, 51% In, 16.5% Sn…
Field’s metal is expensive due to the price of indium, which makes up over half its mass. However, as it contains neither lead nor cadmium, it is a less toxic alternative to Wood’s metal. It is used for die casting and rapid prototyping.
In the video comments, they add:
Why not use Gallium? Well – besides the fact it’s not what we were sent by our fan – Gallium has a very low melting point. It’ll melt in your hand… Not as fun as a spoon that is normal in the hand but then melts in hot water!
With a melting point is 29.7646 °C or 85.5763 °F, you can melt Gallium, a non-toxic metal, in your hand: Get 20g of Gallium on Amazon. You can also buy a Gallium Spoon Mold + 100g of Gallium to make your own spoons.Related videos: Dad teaches his daughter how to cast a ring from scrap pewter, melting metal in your hand, and melting gallium spoon.