Ossein

Ossein is the name given to bones taken from an ovipare that are repurposed in some way. It is used instead of metal due to its natural abundance in the world. The material isn’t viewed as macabre or creepy, it’s treated the way we treat leather or wool. There are many different types of bones from many different types of ovipares, which make for a whole host of uses. Ossein is not obtained from the bones of mammals.

As Coinage
Coins are made of ossein that is sliced into small rounds. The value of a coin depends on the type of bone, and that specific type’s weight. Because each type of bone comes from the same type of creatures, weight and size doesn’t have too much variation. Though there is some. For instance: if you had one lucent that was of standard weight (say, a penny’s weight) and one that was 2x that weight, you would have 3 lucents total. Measured somewhat like the value of gold, for comparison.

When purchasing an item, merchants don’t usually need to use scales to weigh the coins, but they will when you are paying with a lot of one type, or when you have varying sizes. Con artists make a living from selling weighted coins to mess with merchant scales.

The most common denomination, a lucent, is made from the crystalline bones of common fish: the trawl, barrab and pasix fish. These coins are very small in diameter and do not weigh much.  

Brunets are made from the shiny black bones of common lizards. They are much heavier and very sturdy. A brunet is about 5x the value of a lucent of the same weight, though standard sizes are much larger, and means that one standard brunet is equal to roughly 20 lucents.

The filigret is the highest valued denomination. It is a hollow intricate bone that comes from birds. It is more rare and is harder to come by, and keep without breaking. Usually, a person will not travel with filigrets on their person unless they plan to spend them that day. A filigret of the same weight as a lucent is worth about 100x as much. However, they are very small and light so it isn’t common to find a heavier, more valuable filigret like is common with brunets.

This variable value system - three tiers of denomination with flexibility in weight, makes it a highly customizable economy, and allows for trade and bartering.

Because ossein holds veins, muscles, and the other things necessary for a functioning body, they are hollow on the inside. Coins are cut from pieces of bone and strung onto a necklace - called a lavaliere - to keep instead of putting it in a pouch. This is partly for convenience, and partly to protect the coins from cracking or crumbling in a person's pocket.

As Jewelry
Ossein jewelry has long been a staple of fashion across the world. Because of its variety in color, texture, density and shape, its popularity has stayed stable over centuries. Rare ossein jewelry can be found on the hands and necks of monarchs and other highborns as a status signifier or simply as pieces of art.

In the Military
Most armor is made from ossein. Its density, relatively light weight (compared to metal) and tendency to crack instead of dent inwards makes it an advantageous material on the battlefield. Certain types of ossein are used most frequently for this task. The briar monitor has large burr-like protrusions coming from its dense bones, so it is used in the making of weapons such as a morningstar or maul, or even for armor.