Marking is a fundamental process in the precious metals industry and gold being an important aspect in particular. By law, each gold bar, from the smallest to the largest, must be MANDATORILY marked and serialized before being placed on the market. This is done for security, coding and traceability reasons. According to the rules imposed by LBMA (London Bullion Market – the London market for gold and silver) each ingot must have certain specific markings, most importantly, the information of the ingot itself:
Industrial marking or stamping operation, it’s easy to imagine, must not modify the ingot itself in its fundamental characteristics: shape, size and above all, weight. The only technologies allowed in the marking process are therefore those which fully respect these characteristics.
How do you mark a gold ingot?
Among the various marking technologies, the most suitable are the following:
It is the least expensive and, at the same time, a fast and deep marking solution. With both manual or pneumatic operation, and normally used with numbering heads for serialization of the ingot (as shown in the example photos).
Dot peen marking
This technology allows to mark ingots with maximum flexibility, due to the nature of it’s electronic technology and, in particular, being software driven. Being also pneumatic and electric machines, it lends itself to many types of markings: deep, continuous or superficial. It is easily set up to meet specific or in some cases ease of changing marking details.
Scribe marking consists of a tip that “scratches” on the surface of the material being marked, thus producing a continuous line. This technology can only be used on ingots with perfectly flat surfaces.
This is the least used solution, but, thanks to new technologies and new types of lasers, it is considered a valid solution on some processes. It is also a technology that is software driven and guarantees maximum flexibility. Remember, however, that the laser causes an evaporation of the material with consequent possible loss of weight of the material itself.
Not just gold
Marking and coding rules are not only valid for gold bars, but also for silver, palladium, or platinum. These materials must be marked too with the technologies described above.
So how can I choose?
As in all industrial applications, the right strategy is to rely on experienced professionals with a solid knowledge base, application expertise and history.
Automator, since 1940, designs, manufactures and sells marking solutions in all market segments, including precious metals. Automator, through its worldwide team, also provides advisory services to companies seeking the best technology for each type of process and for each type of investment, relying on Automator’s wide range of machines and systems.