In the first post in a series of three winning entries from JM Bullion followers on Facebook, we’re going to take a look at how many of the popular precious metal products that numismatists purchase today are made. From gold and silver bars to Burnished American Eagles, there are various processes used by mints and refineries across the planet to manufacture the gold, silver, platinum, and palladium products that millions by each year. Join us for a look at these varying processes!
Hand-Poured Bars
From the 1 oz Monarch Precious Metals Hand-Poured Silver Bar to the 1 oz Atlantis Mint Skeleton Hand-Poured Bar, there are numerous products available today that market themselves as “hand-poured.” While the name is largely self-explanatory, there is still some room for exploration in the branding of these products in the current market.
As the name suggests, each of these bars started out as melted silver (or gold in some cases) that is poured by hand into a mold that reflects the basic design a mint or refinery is going for. In the case of the Atlantis Mint product referenced above, molten silver is poured by hand into a mold shaped like a human skull.
There are no computers involved in the production of hand-poured bars, and as a result you will often find minor imperfections in the overall finish of the product. Each product will have its own, unique finish because of the manner in which it cools into a hardened form. This, of course, is all part of the allure of hand-poured products.
You’ll notice that many hand-poured bars start with a higher premium over spot because, like a piece of hand-crafted furniture, they have an inherent value that sets them apart from minted ingots. In many cases, depending upon the overall design, hand-poured bars will gain more in value over time compared to minted ingots.
Cast Gold and Silver Bars
Those investors who prefer the London Good Delivery, COMEX Division Good Delivery Bars, and other smaller cast bars chase after a product that exist in a world between hand-poured products and those minted ingots which are highly computerized throughout the production process. Examples of these types of cast bars include the 100 oz Johnson Matthey Silver Bar and 100 oz Engelhard Silver Bar.
The common approach to this production process is to first melt the precious metal in question in a bulk “holding” crucible to prepare it for pouring into molds. Typically an induction furnace is used to heat the metal to its melting point, at which time the holding crucible is tilted to transfer the molten metals through a soft gas flame and into a pre-heated and dressed bar mold to create the bar’s specific size and weight. To ensure proper weights are reached, the molds are typically positioned on a balance to record the weight of the metal as it is poured so that pouring can cease when the right weight is reached.
At this point in the process, one of two steps is taken. Some refiners will drop the bar out of the mold into a tank of water within seconds of pouring the mold to quickly cool the bar in a process known as “quenching.” Alternatively, the bars may be left in the molds to air cool over time.
Either way, once cooling is complete the bars are cleaned with soft cloths to remove any stains and then weighed to ensure the stated weight was achieved in the process. Approved bars are then marked with a refiner’s official stamp, a serial number, and the assayed purity of the batch.
Cast bars are, in the case of minted ingots, actually just the first step in the creation process for an entirely different product.
Minted Ingots
In order to create minted ingot bars such as the 1 oz PAMP Suisse Fortuna Silver Bar, refiners will start by manufacturing long, flat cast bars to serve as the blanks upon which minted ingots will eventually be formed. Traditionally this was done by creating a long mold that was used in the production of cast bars. These molds made it possible to create cast blanks with the precise width, thickness, and length required to make minted ingots.
To speed up the process, modern refiners will often use a continuous casting process instead. This produces bar stock of the required width and thickness on a continuous basis that is then fed into a continuous casting machine. Throughout a very complex process, the cast blanks are melted under induction heating or resistance heating to form minted ingot shapes that match exact specifications.
The new bars are then broken down in a rolling mill to reduce the larger batches down to the required thickness, and an interstage annealing process occurs that recrystallizes the grain structure of the metals and improves the surface finish of the bar. The rolling mill, combined with a strip annealing furnace help refine the bars to their required thickness. Further exposure to a gauging mill refines the bars even more, before they are eventually sent to the blanking press where each individual bar is punched out of the strip to prepare for striking process, at which point mint marks and designs are added to the finished product.
Burnished Coins
To a certain degree, all coins and rounds start out the same way. A mint or refinery will create blank silver or gold coins/rounds to use in the eventual production of a bullion or proof coin. The purity and weight of each individual coin or round is up to the production mint, but those blanks are eventually fed into coining presses and struck with a die to create the beloved coins and rounds that investors and collectors purchase in droves.
However, within this system there are certain differences in production that provide an altogether unique finish to products. Two worth highlighting are the ½ oz Monarch Egyptian Round and the Burnished American Silver Eagle coin. In the case of the former, the design applied to the ½ oz Monarch Egyptian Round is entirely unique in that the rounds are struck with a die to be off center on purpose. Monarch Precious Metals wanted to create a silver round that reflected the best of modern production methods, but the time-tested creation of coinage that dates back thousands of years.
When it comes to the Burnished American Silver and Gold Eagles, one of the most intensive coining processes in the world is followed. On the surface, the production process of the burnished coin is similar to that of the proof coin. Both products are struck with an eye toward producing a coin with refined visual features and sharper rims. Dig a little deeper though, and you’ll find that the Burnished American Eagle coin undergoes a more specialized striking process to ensure the coin’s visual brilliance is beyond reproach.
The striking of a Burnished American Eagle starts with unique blanks, also known as planchets. These blanks start out as the same blanks used for the production of the proof version of the American Eagle. The blanks are loaded into a rotating drum before striking to undergo a polishing process. Large volumes of blanks are placed in the drum with a polishing media. Historically, wet sand was used by mints to polish blanks for the production of burnished coins. Today however, the US Mint uses millions of tiny 6 mm balls to polish the blanks.
Continued friction caused by the rotation of the drum and the collision of blanks and balls creates the smooth, matte-like surface found on the burnished coins. Once the rotating drum is done polishing the Burnished American Eagle blanks, each one is removed individually by hand by US Mint handlers wearing white gloves. This is done to avoid defacing the coin’s surface with oils and dirt from human skin. The blanks are then individually loaded into the striking machine to produce the stunning look of the American Eagle. The coins are then removed by gloved hands, inspected, and immediately packaged in plastic slabs and shipped with a Certificate of Authenticity.
A Note on Production
In this post, we’ve offered a broad overview of a very complex process that can differ slightly from one mint or refinery to the next. In reality, each mint or refinery in the world has some special little touch that sets their product apart from the competition. What we’ve done is give you some insight into the traditional and common modern production process for some of the most popular products available on the market today.
Thanks to Scott Mitchell!
JM Bullion recently reached out to our followers on Facebook asking them what they wanted to know about their beloved precious metal products. From a contest in which we eventually chose three winning concepts, Scott Mitchell’s request to know more about the production of some of today’s precious metal products was selected as the winner and accordingly written about first. Congrats again Scott, and thanks to all of our followers on Facebook!