HomeGold BullionGold BarsPoured Gold Bars
There are many different types of gold bars available to investors today. These gold bars will vary in weight, purity, manufacturer and premium. In addition, the way in which gold bars are actually minted differs as some bars are “pressed” while other gold bars are “poured.”
The term poured gold bar refers to gold bars that have been manufactured by pouring molten gold into a mold. Another term for poured gold bars is “cast gold bars.” Poured, or cast gold bars, differ from other types which are manufactured from a sheet of blanks and then stamped. Here we will examine the process of casting gold bullion bars. There are essentially three different types of cast bars. These types are: large cast bars that have approximate weights, small cast bars with specific weights and long, flat cast bars used for the manufacture of minted bars.
Large cast bars are manufactured to be an approximate weight and are considered good delivery for London 400 ounce and Comex 100 ounce gold bars. Refined gold that is of the necessary purity is melted in bulk in a crucible. This crucible can contain amounts of gold as small as 450 ounces or as large as 30,000 ounces. The crucible is then tilted in order to pour a small amount of gold from 450 ounces to 2000 ounces into a pre-heated crucible. Once this is done, samples may be taken from the crucible for assaying purposes.
The gold in the transfer crucible is then poured through a soft gas flame into a pre-heated bar mold. These bar molds are typically made from cast-iron and come in various sizes such as 100 ounce, 400 ounce etc. The bar mold is placed on a balance during pouring. The balance is used for recording the amount of gold being poured into the mold. Once the appropriate weight of gold has been distributed, the process stops.
Following this process, the mold is then immediately tipped so the gold bar falls out and into a tank of water to cool. Some manufacturers may allow the gold bar to remain in the mold during the cooling process. Once cool, bars are cleaned and examined. Assuming the bar has the proper weight, it is then marked with the refiner’s stamp, a serial number and the assayed purity of the gold. The gold bar markings can be applied by hand or by a stamp.
Small cast bars are bars that must be a specific weight and are less than 1000 grams. These bars are made by taking gold that has been assayed and turning into granules or small cut pieces or strips. Once the gold has been turned into small pieces or granules, it is placed on the balance to measure the precise amount of gold needed to make the bar. The small pieces or granules are measured in either a crucible or bar mold. Once the correct amount of gold has been determined, the crucible is placed into a furnace in order to melt the gold. Once the gold has melted and reached the appropriate temperature, it is then poured quickly into a pre-heated bar mold. Markings on these gold bars are typically applied by stamping, although they may also be applied by hand.
Long flat cast bars are made for the production of minted bars and can be manufactured in two different ways. These are by casting machines or ion cast-iron mold packs. The cast-iron mold pack is considered to be the more traditional method. Machine casting is the more modern method. In the machine casting process, the machine has a die that is cut to the necessary thickness and width of the gold bars to be produced. Gold is heated in an attached crucible. Once the gold has reached the correct casting temperature, the bar in the die is slowly pulled out in several movements this allowing the molten gold to enter the die and take the appropriate shape. Gold solidifies as it passes through the die. The gold is then cut to the desired length. The process is made continuous by adding additional gold granules or pieces to the crucible.
Poured gold bars have a distinct look and natural finish. The bars have more of a vintage or worn look to them as opposed to other, newer manufacturing methods. In addition, because of the way poured gold bars are made, they may have intricate designs and detail. Poured gold bars are produced by various manufacturers and come in different sizes including the 100 Gram PAMP Suisse Bar.
Pricing for poured gold bars varies by manufacturer and purity. Generally speaking, poured gold bars may have higher premiums over the spot gold price associated with them. This is because of the additional work and detail that goes into producing these bars.