Bismuth - a surprisingly rare metal

Bismuth - a surprisingly rare metal

Bismuth (Bi) is a metal (though sometimes classified as a metalloid) best known for the beautiful crystals if forms when cooled from a liquid state. Other uses for metallic bismuth are rather limited, usualy replacing lead in applications where a toxic metal is not an optimal choice, such as soldering, fishing or hunting.

Being only around as abundant in the Earth's crust as silver (Ag), such metal is not a resource to be implemented widely in such mundane tasks anytime soon.

Bismuth metal pieces.

Pure metallic bismuth is a silvery, shiny metal that oxidizes on air when heated. Otherwise Bi is classified as highly unreactive metal, just below copper and mercury. It is also surprisingly brittle and can be broken up by hand. That makes it useless in structural roles, at least in the pure, unalloyed form. Reagent grade bismuth can be bought in the form of small, needle-like drops or bigger bars that can be broken into smaller pieces.

Vanadium - the secret hero of metallurgy

 Vanadium - the secret hero of metallurgy

Vanadium (V) is the lesser known among the lighter transition metals, located between the popular titanium (Ti) and chromium (Cr) it kind of gets overshadowed. The importance of vanadium, however can not be overstated. It plays a huge role in improving hardenability, tensile strength, tribological wear resistance and hardness of steels.

Pure V crystals.

An ampoule of V crystals.

Neodymium - the most popular of rare earth metals

Neodymium - the most popular of rare earth metals

Neodymium metal is generally very well known, compared to it's cousins from lanthanides row - ask a random person about neodymium and they will probably at least recognize the name from somewhere, whereas thulium (Tm), gadolinium (Gd) or dysprosium (Dy) would most likely be a different story.

Pieces of neodymium metal under paraffin oil.

The main reason why is not the metal itself, but neodymium magnets, which will be talked about a bit later. Pure neodymium in it's metallic form is a shiny graish-yellowish-silver metal, which oxidizes rather rapidly on air, firstly getting covered with a dull black coating, which as time passes flakes off into what looks like a pink colored dust that serves no purpose in keeping the metal from further oxidation. 

The pink dust is Nd2O3, neodymium oxide that is often utilized in ceramics or glass making.

Neodymium glass bottle.

Nd3+ doped cubic zirconia stones

When added to glass, neodymium on +3 oxidation state dyes it purple-violet color that turns sky blue under fluorescent light. Similiar coloring can be observed on synthetic zirconia stones. Those look lighter and clearer than the traditionally dyed purple zirconias doped with manganese (Mn) ions.

Small cylindrical neodymium magnets in a jar.

Neodymium, sometimes called also rare earth magnets (that groups contains also Sm-Co magnets), are an alloy of iron, neodymium and boron. Due to their brittleness, these magnets are usually coated with a thick layer of nickel (Ni). An addition of dysprosium (Dy) can also be used to improve such magnet's resistance to demagnetisation. 

Nd2Fe14B magnets are currently the strongest permanent magnets available and can be purchased in many different sizes. Small 2x2 cylindrical magnets, like the ones pictured, are popular among 3D printing enthusiasts for adding magnetic locks or creating satisfying fidget toys etc..