- Posted in: Custom Mint
One would not typically question the origin of the coins sitting quite nonchalantly in their pockets or cup holders, but for the exclusive Chris Kyle Frog Foundation coins,the coin enthusiasts at GMR have undertaken the task of documenting the process of creating the special commemorative series items.
GMR has teamed up with Great American Mint to mint the coins, and BEX Engraving to create the dies.
It Starts with the Art
After selecting the chosen design that will be featured on both the front and back of each silver, and copper coins as well as the silver bar, a graphic designer renders the design in a vector file. Once the files have received final approval, the engraving process can begin!
Using the vector files for the Obverse and Reverse of the products, a black and white master is created and photo processed to velum polymer plate. This creates a reverse image that is 4 times the size of the coin.
Trace, Trace, and Trace Some More
Using the polymer plate, a master engraver then begins the meticulous and detail oriented job of tracing the image to render it on a base using a pantograph machine. A pantograph is an instrument for copying a drawing or plan on a different scale by a system of hinged and jointed rods. The system used by the engraver is an industrial sized and precision accurate machine designed to take the larger reverse image and scale it down to the base of the die.
Spinning at 30,000 rpms, the steel tool, or cutter, can then begin etching the traced design into the steel base. Shown to the left, the engraver can be seen tracing the American Flag reverse shown on the back of the Chris Kyle Frog Foundation commemorative coins in the background, while the smaller rendering appears in the foreground.
A Little Bit of Heat
The rendered base is prepped for the heating process by a stoning or polishing process to ensure that the die is set correctly. After the polishing the base undergoes a heat treatment that hardens the steel and prepares the die to render coins at 150 to 200 tons of pressure exuded during the minting process!
A final polishing procedure is then applied to the treated die to ensure the surface can create a clear and perfect representation of the desired image. The process begins with a glass beading, and stoning polish; afterwards the dies are covered with a diamond paste and further polished using a felt bob to polish and treat the dies to withstand the tremendous job they have in store for them!
To ensure that the proof coins retain the highest quality Chris Kyle Frog Foundation commemorative coins and bars, the dies will be periodically changed–and the process will begin again!