When you say the word hallmark, most people would probably imagine a greeting card. But hallmarks actually were (and still are) the small, inconspicuous mark stamped on precious metals. When it comes to buying a piece of jewellery, the hallmark represents important information to the customer about the authenticity, origin and purity of the piece of jewellery it is stamped on. For rings, it is usually stamped on the inside (or shank) of the band, for earrings on the shaft, and for chains, at the fastening.

In fact, there are three different types of marks that appear on jewellery, namely the government hallmark, then the fineness or purity mark as well as the identification mark. Not all three need to always be present on a piece of jewellery. The Convention on the Control and Marking of Articles of Precious Metals is in place in the Czech Republic and it clearly spells out the rules for manufacturers and suppliers of jewellery.

Engagement and wedding ring with diamonds rose gold KLENOTA

Marking purity

For gold:

  • 585/1000 – 14-carat yellow gold – 585 pure gold parts + 415 parts of other metals;
  • 750/1000 – 18-carat yellow gold– 750 gold parts + 250 parts of other metals;
  • 999/1000 – 24 carat gold – pure gold – contains no additives. Pure gold jewellery is usually not produced because the gold is too soft for jewellery hence right away there is wear or damage.

For silver:

  • 925/1000 – most often marked as 925  

Hallmarking symbols for purity

Hallmark types

  • state hallmark (hallmark guaranteed by the state)
  • purity hallmark (number specifying the ratio/purity of metal)
  • production hallmark (name of manufacturer who made the product).

The Government hallmark

In many countries such as the UK and the Czech Republic, the government hallmark (a pictorial stamp on the metal) represents an independent checking mechanism for jewellery. This pictorial symbol specifies the type of metal which the jewellery is made from, its purity, and also the approximate age of the jewellery.

Jewellery made in the US cannot carry such an official government hallmark stamp since the US does not have a government regulated hallmarking system for jewellery. It instead has a number of private, independent assaying agencies in various states and cities which stamp their own marks.

Official hallmark symbols have evolved over time, so you will find a different hallmark on your grandmother's jewellery than the one which is on new jewellery. From hallmarks currently in use, it is also possible to work out which workplace the hallmark was stamped at. In the Czech Republic, the hallmark on jewellery is stamped by the government Assay Office and is mandatory for all gold jewellery where the weight of pure gold in it is greater than 0.52 g, as well as on silver jewellery which weighs more than 3.49 g.

Gold KLENOTA jewellery

These are the most common types of Czech hallmarks that you may come across:

Identification marks

The origin of a piece of jewellery is disclosed on what is known as a maker’s or sponsor’s mark. In many countries which have official government hallmark regulations for jewellery such as in the Czech Republic, these maker’s marks can look different. In the Czech Republic, they come in two varieties. Every jeweller or company which produces jewellery and which is registered with the government Assay Office has its own unique form of the stamp and this is called the maker’s or sponsor’s mark.

If it is an entity that imports or buys the jewellery from abroad and then sells it in the Czech Republic, then even that process and jewellery does not escape the official government hallmarking requirements. The Assay Office will then assign to it a “responsibility” or import mark. Stamping each piece of jewellery that goes on sale is the responsibility of each owner of these identification marks.

You will find a full list of these identifying markers on the government’s Assay Office website. All KLENOTA jewellery carry the following maker’s mark stamp in the form of the letters KLE in an oval:

Fineness or purity marks

The third type of mark is a fineness or purity mark, known in the UK as a “standard mark”, which takes the form of a three digit numerical code. It is used for quick orientation regarding the type and purity of the metal from which the jewellery is made. For gold jewellery, you will most often encounter the code 585 or 585/1000, which indicates 14 carat gold. This combination of numbers is not as random as it might seem at first glance. The amount of precious metal is stated as a fraction of a thousand and in that alloy, there is 585/1000 of gold. Converted to a percentage, there is 58.5% of gold in the alloy. For 18 carat gold, the code 750/1000 is used, which also indicates that that particular metal contains 75% gold.

Contemporary silver jewellery usually carries the stamp 925/1000, which indicates that the metal is sterling silver. It has 92.5% of pure silver in it and only when combined with another type of metal, most often with copper, does it become stronger and more durable. Stamps of lower purity, such as 800/1000, may be found on older jewellery or on utilitarian items.

studio KLENOTA

While on some pieces of jewellery you will find all three types of marks, this is not a necessary requirement. If a piece of jewellery is stamped with the government hallmark, it no longer needs to be marked with a fineness or purity stamp, since that information is also on the government stamp. Also, some jewellery is not required to carry the government hallmark due to its lower weight. In such cases however, in the Czech Republic at least, the jewellery must have a fineness or purity mark.

We are a registered dealer with the Assay Office

On August 24, 2008, KLENOTA Jewellery concluded an agreement with the government Assay Office on enabling quality assurance purchases for the purpose of online sales. Based on this agreement, the KLENOTA Jewellery store / KLENOTA s.r.o. company is on the list of signatories to the agreement which the Assay Office publishes on its website. The Assay Office regularly checks the compliance of dealers with government regulations and legal requirements. In other words, it assures a level of quality of all dealers.Registrovaný obchod puncovním úřadem