UA is UniArt's registered jewellery brand. Each UA silver piece is made from 925 sterling silver, assayed by an official Spanish assay office and stamped with the UA mark alongside the official guarantee hallmark.
UniArt Sterling Silver Guarantee
All UniArt (UA) products described as sterling silver or 925 silver have a minimum silver fineness of 925 parts per thousand and bear the official guarantee hallmarks.
Official guarantee hallmarks:
Under current Spanish legislation, silver articles must undergo rigorous inspection by an official precious metals assay office before being offered for sale.
The assay office determines the fineness of the metal, meaning its purity, and stamps the piece with its official guarantee hallmark, which contains the fineness in figures followed by the assay office's identifying code. The piece must also bear a sponsor's mark, an official mark identifying the manufacturer or importer.
These two marks are known as hallmarks.
The guarantee hallmark for sterling silver is a rectangle containing the number 925 followed by the authorised official assay office's identifying code (a letter and a number).
The sponsor's mark is a corporate mark identifying the manufacturer or importer. It has official status because it is recognised by the competent authorities.
UA (UniArt) sponsor's mark:
Examples of official guarantee hallmarks:
UA mark stamped on a piece alongside the official 925 guarantee hallmark:
We recommend using a magnifying glass to see the marks more clearly.
If, for technical reasons or because of its size, a piece cannot be properly hallmarked, the assay office will provide a label bearing the relevant marks. This label must always accompany the piece to guarantee its fineness.
Guarantee labels may vary in format, content and material, but all bear the official hallmarks.
Pieces guaranteed in accordance with the legislation carry a lifetime guarantee of their silver purity. The assay office and the manufacturer or importer are responsible for the accuracy of this guarantee and the purity of the metal.
Sterling silver or 925 silver
As pure silver is a very soft metal, it needs to be mixed with another metal to make it suitable for working, creating an alloy.
In Spain, the law recognises alloys containing 92.5% silver and 7.5% another metal, usually copper, as first-standard silver, known in English as sterling silver.
Second-standard silver is an alloy with a lower silver content of just 80%.
To define silver purity, these percentages are expressed in parts per thousand: 925 for first-standard silver and 800 for second-standard silver.
If analysis by the assay office shows that an article does not meet the required fineness to qualify as silver of a legally recognised standard, it cannot be offered for sale and the assay office will not hallmark it.
To qualify as sterling silver, an article must therefore be made from an alloy containing at least 925 parts per thousand of silver: at least 925 parts silver and no more than 75 parts another metal.
Other marks that pieces may bear:
The only marks that guarantee the purity and quality of silver pieces are those mentioned above. Pieces may also bear other marks considered promotional, but these have no official status.
Please note that counterfeiting official hallmarks is considered a very serious offence.