Master Alloy for Jewelry Application

All our high-quality master alloys come from W.R. COBB (USA). With state-of-the-art production lines and auxiliary machinery in both China and Hong Kong factories, we manufacture various kinds of sterling silver with first class master alloys from W.R. COBB (USA) to meet different requirements, e.g. enhancing tarnish resistance, improving mechanical properties, modifying brightness and color, etc.
Our master alloys include,
i. Gold master alloy
– Master alloy for white gold
– Master alloy for white gold (nickel free)
– Master alloy for yellow gold
– Master alloy for red gold
ii. Sterling silver and silver master alloy
iii. Coloured silver
iv. Brass and bronze alloy
Our patented brands of white gold alloy and sterling silver, i.e. Precise® White Gold & Precise® White Silver, have been well-known to our customers from around the world. In 2018, we officially launch new series of gold master alloys, sterling silver, silver master alloys, coloured silver and brass/bronze alloys to meet market demand.
Master Alloy for White Gold
White gold alloys were originally developed as substitutes for platinum, and they are commonly used in the jewelry industry. A variety of master alloys for white gold are available in COBB and Lee Metals Trading Company Limited to suit specific needs.
We are proud to provide our customer with our exclusive Precise® White Gold, a patented brand of master alloy for white gold from W.R. COBB (USA). The Precise® White Gold is known for being a true white gold because of patented alloy formula. The typical yellowish tinge that is common in white gold has been eliminated, leading to a higher customer satisfaction. The Precise® White Gold exhibits following superior properties,
– Exceptional cast brightness
– No need to use rhodium plating
– No yellow tinge commonly seen in white gold
– Excellent hardness
– Retained ductility for diamond setting & hand fabrication
– Lower manufacturing costs
Our master alloys for white gold are available in 10 Karat, 14 Karat and 18 Karat options.
Master Alloy for White Gold (nickel free)
For customer concerning about the nickel content of master alloys for white gold, COBB and Lee Metals Trading Company Limited can provide another option to meet their needs by offering several kinds of master alloys for white gold (nickel free). Palladium is utilized to substitute nickel in this series of master alloys for white gold (nickel free) and therefore all of the master alloys for white gold (nickel free) are in compliance with EN 1811:2011.
COBB and Lee Metals Trading Company Limited can provide several master alloys for white gold (nickel free) covering a range of different palladium content for selection. The master alloys for white gold (nickel free) are available for 10K, 14K and 18K casting. Customers can benefit from using the nickel-free master alloys for white gold to fulfill nickel requirements of different countries.
Master Alloy for Yellow Gold
Yellow gold is the only type of gold that can be used in jewelry making as 24-karats. Due to the softness of the 24-karats yellow gold, different master alloys are needed to enhance and modify physical and mechanical properties of the yellow gold, e.g. increasing hardness. As such, COBB and Lee Metals Trading Company Limited are pleased to introduce a line of premium master alloys for yellow gold to our customers. Our master alloys for yellow gold feature the following properties,
– Excellent reusability
– Excellent fluidity
– De-oxidized
COBB and Lee Metals Trading Company Limited can offer master alloy for 10K, 14K and 18K yellow gold.
Download Product Sheets
Data Sheet Y107 Master Alloy for Yellow Gold
Data Sheet Y173A Master Alloy for Yellow Gold
Data Sheet Y310C Master Alloy for Yellow Gold
Data Sheet Y505 Master Alloy for Yellow Gold
Data Sheet AGM 4002 Master Alloy for Yellow Gold
Data Sheet AGM 6005 Master Alloy for Yellow Gold
Data Sheet AGM 9001 Master Alloy for Yellow Gold
Master Alloy for Red Gold
Red gold is widely adopted in manufacturing specialized precious jewelry. It becomes popular and commonly used for wedding rings, bracelets and other jewelry. With the increase of demand in red gold in jewelry market, COBB and Lee Metals Trading Company Limited are pleased to provide different kinds of master alloys for red gold, which are formulated and tailor-made in factories of W.R. COBB (USA), to meet specific needs and requests.
Our master alloys for red gold provide the following advantages,
– Excellent fluidity
– Brilliant red/rose colour
– Good reusability
– De-oxidized
COBB and Lee Metals Trading Company Limited covers the range of master alloys for 10K, 14K and 18K red gold.
925 Sterling Silver and Silver Master Alloy
With the use of master alloys for silver from W.R. COBB (USA), COBB and Lee Metals Trading Company Limited can manufacture and provide sterling silver for our customers through using advanced technique and equipment in our factories of Hong Kong and China.
Our patented Precise ® White silver, which is made with using our master alloy for silver, is one of the sterling silver that we can provide. It exhibits following properties,
– Exceptional cast brightness compared to traditional silver
– No need to use rhodium plating
– Excellent tarnish resistant
– Reduced fire scale from casting and a finer crystal structure compared to standard sterling silver.
In 2018, COBB and Lee officially launches a new series of master alloy for functional sterling silver. Our new functional sterling silver ASM 1101-928 and ASM 1102-928 can offer the following properties,
– Suitable for casting, rolling
– Enhanced ductility for sheet and wire
– Excellent cast brightness
– Good tarnish resistance
Download Product Sheets
Data Sheet PWS 928 Sterling Silver
Data Sheet ASM1101 Sterling Silver
Data Sheet ASM1102 Sterling Silver
Data Sheet Cu430 Silver Master Alloy
Data Sheet Cu1 Silver Master Alloy
Data Sheet ASM1103 Silver Master Alloy
Data Sheet ASM1104 Silver Master Alloy
Data Sheet ASM1105 Silver Master Alloy
Coloured Silver
In addition to sterling silver and master alloys for silver, COBB and Lee Metals Trading Company Limited officially introduces our new line of specialized coloured silver to the jewelry industry. Different kinds of coloured silver are made available for our valued customers. The coloured silvers include,
– Pink coloured silver
– 14K yellow coloured silver
– White bronze coloured silver
With properties of excellent brightness, excellent metal flow, good casting properties, and enhanced tarnish resistance, our customers can definitely benefit from the unique properties of the coloured silver to make costume and imitation jewelry.
Download Product Sheets
Data Sheet ABB 1000 White Bronze silver
Data Sheet ASC 5005 Pink Silver
Data Sheet ABB 4004 Yellow Silver
Brass and Bronze Alloy
There is a lack of high-class and good-quality brass and bronze alloys in the market. And only regular brass and bronze are available for the jewelry industry to make non-precious jewelry. As such, COBB and Lee is pleased to provide our customers who manufacture non-precious jewelry and fashion accessories with a wide range of high-class brass and bronze alloys. The brass and bronze alloys have featured properties of excellent metal flow, enhanced tarnish resistance, good plating properties. Our customers can make use of the specialized brass and bronze alloys to make costume jewelry and fashion items.
In addition, our brass/bronze alloys are manufactured in different colour, e.g. pink, 14K yellow, greenish yellow, white, true bronze colour, etc., to suit your specific design needs. Customers can enjoy the benefit of using our brass/bronze alloys to design and make fashioned, high-class and good-quality non-precious jewelry.