One of the amazing things about dice is how many variations of styles there are, so we decided to take a deeper look into all of the different dice options in existence and how they're made! In our first article, we're going to be looking at all of the different materials dice are commonly made from.
Plastic Dice
Synthetic Urea
Synthetic urea is a common material used in mass producing dice, typically cheaper ones used for board games. This injection-molded material is easy to work with, but doesn't offer much variability in color and style. It tends to be fairly lightweight and is without great edge definition in the final pieces.
Acrylic (PMMA)
Before the last 5-10 years, almost all “fancier” dice were made of acrylic, and it remains an extraordinarily popular material for dice production. Acrylic comes in a wide variety of colors, and it’s possible to use dyes and multiple colors of acrylic to achieve fun swirled patterns, along with effects like glitter. Acrylic dice start as a plastic pellet that is injection molded into what's called a family mold, consisting of 10-15 total dice in a single mold. From there, the sprues are cut off, and the dice are tumbled to produce an even, clean finish, which is then painted. Finally, they're tumbled a second time to polish the dice and remove any excess paint, as well as provide a nice, clean finish.
Resin
Unlike acrylic and urea, resin dice aren't injection molded - resin starts as a 2-part liquid that is mixed together and then poured into large silicone molds before being allowed to set. Because of this, many more techniques are possible - complex color swirling, layering, and more can all be accomplished by considering how you mix multiple colors together and if you allow one layer to start to set before adding an additional layer. Commercial resin dice are made with an open mold - the top is simply left open, allowing extra resin to fill in as it shrinks slightly while setting. After being given several days to set, the empty face is sanded to the correct height, the '1' is laser-engraved on, and then the dice are painted and polished, much like acrylic dice.
In many ways, resin dice have changed the entirety of the industry - whereas most dice looked very similar before, there are now a nearly infinite number of techniques and styles that are possible.
Resin With Inclusions
Because resin dice are poured and then set, there is an opportunity to add items during the process. For inclusion dice, the bottom portion of resin is poured and allowed to begin to set before a small, painted resin figure is added. Resin is then filled to the top of the mold, sealing the small figure inside. Since both the inside piece and the outside are made of similar materials, there is no significant weight difference where the inclusion is, allowing these to continue to be balanced.
Sharp Edged Resin
Another awesome thing about resin dice is that there are multiple finishing options! In addition to tumbling them, it is possible to polish and paint them entirely by hand. By doing so, you can achieve a nearly glass-clear finish that shows off the interior and any inclusions extraordinarily well. While this process is time-consuming, it produces dice that are stunning to behold.
Liquid Core Resin Dice
Another technique that is only possible because of how resin dice are made is liquid core dice. These are produced similarly to inclusion dice, except the included item is a small glass bauble filled with a liquid (typically oil or alcohol) and glitter. Because this liquid remains even when the resin has set, you can shake it or roll it and see the glitter move, similar to a snow globe.
Metal Dice
Cast Metal Dice
The majority of metal dice on the market are made using the same technique - a base metal consisting of zinc and other elements is cast into molds before being electroplated, painted, and then polished.
Hollow Metal Dice
Hollow metal dice are made by wax inclusion casting. A wax version of the die is produced and is packed to make an extraordinarily precise mold, which is then filled in with brass. This allows for very fine detail and an empty interior. The dice are then electroplated and painted if the design calls for it; sometimes a light dye is applied to the whole die to highlight the details of the design.
Machined Metal Dice
Very high-end metal dice are made by using a computer-controlled cutting device, a CNC router. A rectangular blank is placed on this cutter and it is able to move in 4 or more dimensions (Up/Down, Left/Right, Forward/Back and one or more turning angles). The design is precisely cut out of the blank material and the numbers are either cut out during this step or laser engraved as a finishing step.
Other Materials
Semi-Precious Stone and Glass
Semi-precious stone and glass dice are made in the same manner as machined metal dice. Blanks of glass or semi-precious stone (typically lab-created, not naturally occurring) are cut using a CNC cutting machine. Lab-created materials are used in order to reduce the variance and imperfections within the stone to help improve balance and durability. With natural stone, it is important to avoid any imperfections that might cause it to crack easily or not correctly form a die shape, so sometimes a machine is used to test for them and avoid them in the cutting process.
Wooden Dice
Wood dice are typically made of a composite material—wood has resin or some other kind of filler added to it to close any gaps and give it a stronger structure in every direction. Then, it is CNC cut and painted to produce the final product.