Do you know why 24k gold jewellery is not for sale?
Because pure gold is very flexible and ductile.
The solution to make it usable is to add alloy to it.
But what is alloy?
Alloy is the mixing of two or more materials to achieve one or more of the following objectives:
- Reduce costs by decreasing the amount of pure metal;
- Increase or decrease strength and hardness;
- Lower melting point;
- Change hue.
What metals are alloys made from?
The alloys for yellow, rose and green gold are formed by silver and copper.
While for white gold the alloy used is palladium or Star alloy or other brands.
What is touch?
It is the permillage of pure precious metal in an alloy.
The gold touches most commonly used by jewellers are:
Gold (touch) 800 or 19.2 k: this gold contains 25% of alloy. In other words, the piece has 80% of pure gold. It is widely used in Portugal.
750 or 18 k gold (touch): this gold contains 33.33% of alloy. In other words, the piece has 75% of pure gold. It is commonly used in Europe.
Gold (touch) 585 or 14 k: this gold contains 70.94% of alloy. That is, the piece has 58.5% of pure gold. It is commonly used in the Orient.
Gold (touch) 375 or 9 k: this gold contains 166.66% of alloy. In other words, the piece has 37.5% of pure gold. It is commonly used in the Orient.
Attention: all these gold toques can be produced and sold in Portugal as long as they have the certification of the Mint, with the indication of the ring and type of material and the Punch of the manufacturer.
A gold piece with a 800k or 19.2k purity will have a higher value as it contains more pure gold than gold pieces with a 750k or 18k purity, than gold pieces with a 585 or 14k purity or 375 or 9k purity.
In the link below you can find which is the legal mark of the Portuguese "Contrastaria" with which the jewellery piece will be marked, identifying the precious material and its touch.
Pure gold: 24 carats or 999
Jewellery made to shine - Missian Jewellery