PRECIOUS METALS: GOLD, SILVER, PLATINUM AND PALLADIUM
The characteristics as precious metals for being:
- chemically stable/low reactivity to acids, oxidation and corrosion;
- flexible/ ductile (can be compressed or stretched without breaking);
- are rare and/or scarce;
- are quoted on the market - commodities.
These metals have several industrial applications due to their good electrical conductivity and resistance to oxidation and corrosion.
Gold and silver are widely used in electroplating and electroplating processes.
These processes are used in jewellery mainly for decorative purposes.
Palladium was introduced in 2015 in the new Legal Regime of Goldsmiths and Contrasts(RJOC), as a precious metal.
Pure 100% GOLD, SILVER and PLATINUM cannot be used in jewellery and other utensils as they are flexible/ ductile.
To enable them to be used for these purposes, they add the alloys to them.
What are alloys?
League 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.
We call the permilage(%º) of pure precious metal in an alloy Touch.
GOLD - SILVER - PALLADIUM - PLATINUM
Official titles of the assay officesStandard" levels of pure precious metal, expressed in permillage, designated by the Assay Offices as reference in the assay and marking of pieces. These levels apply to the entire national goldsmith's / jewellery sector, through the "Regulamento das Contrastarias".
OFFICIAL TITLES OF CONTRASTS |
GOLD SILVER PLATINUM PALLADIUM |
999%o(24 Carat) 999%o 999%o 999%o |
916%o(22 Carats) 925%o 950%o |
800%o(19,2 Carats) 835%o 900%o 500%o |
750%o(18 Carats) 830%o 850%o - |
585%o(14 Carats) 800%o - - |
375%o(9 Carats) - - - - |
"Ouro de lei" : expression of Portuguese origin, applied essentially to gold of 800%o touch, the standard touch of gold used in Portuguese jewellery until 2003.
TITLE % LINKS TO BE ADDED |
999%o(24 Carat) 0% |
916%o(22 Carats) 9,17% |
800%o(19.2 Carats) 25% Most used in Portugal |
750%o(18 Carats) 33.33% Common in Europe |
585%o(14 Carats) 70,94% Common in the East |
375%o(9 Kilates) 166,66% Common in East |
GOLD - SILVER - PALLADIUM - PLATINUM
Jewellery inspired by royalty! - Missian Jewellery