2021-05-22: Zn, Y, Mo, Dy, Ho

In January I made a post depicting several samples that I had received in my personal quest to collect all of the 83 naturally-occurring chemical elements. Recently, my spring shipment arrived. A company called Metallium has for over a decade sold elements and chemicals inexpensively online, and they are most well-known for their series of Element Coins, a unique line of penny-sized coins made from each of the chemical elements.

Yttrium, the 39th element, is classified variously as either a rare-earth metal or a transition metal due to its chemical behavior. It's relatively light and stable in air, and has a dark hue typical of rare-earths.

Molybdenum is a hard and heavy transition metal. In the periodic table, it sits next to technetium, the lightest radioactive element, and beneath chromium, with which it shares its deep luster. Due to the metal's hardness, the imprint on the coin is notably shallow.

Dysprosium is a rare earth metal, one of fourteen to sixteen metals known for their incredibly similar chemical properties and mild reactivity. Dysprosium is somewhat stable in dry air and has a slight greenish hue typical of rare-earths.

Holmium is another rare-earth element, found next to dysprosium on the periodic table. Due to the metal's vague brittleness, the coin's edges are very rough. Its surface also has a certain roughness unlike the other coins, but this may be due to oxidation.

Continuing my collection of the larger (and more expensive) element rods, I also received a rod of pure zinc. Zinc is a fairly common metal, used in the cores of pennies, which is fairly toxic. The metal has a slight bluish hue, which is visible in this image but more pronounced compared to other rods.

In January, I photographed coins through their protective containers, but home in the dry New York air I was able to remove them. Sulfur is the most delicate of the coins; moving it leaves behind small fragments of the element.

Selenium showed extensive signs of some sort of oxidation even before removing it from its container, something I hadn't expected or read about. Its deep blue-black color is very evident in this image.

Erbium is one of the most chemically stable rare-earths. The fairly dense metal shows a strong green coloration which can be faintly seen in this shot.

The complete collection so far, laid out in a periodic table shape (albeit with many gaps). This includes coins, rods, other samples (a pellet of beryllium, buttons of americium), and chemical stand-ins (fluorite for fluorine, salt for sodium, the battery for lithium). I hope to see it expand and the gaps get filled in the future.