JEWELLERY METALS
Diamond jewellery can be paired with a variety of precious metals. The metal you choose can depend on your preference in durability, look and cost. Factors that set different types of metals apart are also the lustre (shine), weight and colour of the metal. Here at NB Jewellers® we craft jewellery using gold, and platinum. We are also committed to using eco-friendly sources of metal. These are among the most durable and visually appealing metals and are most commonly used in crafting jewellery. These metals are classified as precious as they are rarer and more expensive than other used metals.
Gold
A large portion of jewellery is forged with gold and this has been the case for centuries. Gold offers versatility in hue. It is available in white, yellow and rose shades most commonly. White gold is a great match with all gemstones and diamond and offers a versatile shine. Yellow gold is more traditional and pairs well with coloured gemstones as well as diamonds. Finally, rose gold is a striking pink hue and unique choice.
Platinum
A precious metal, platinum is more expensive and rarer than gold. Platinum has a silvery white hue and is known for durability. Platinum is often chosen for its ability to resist abrasion or scratches. This fine metal pairs well with any gemstone or diamond. It is best used for jewellery like rings and wedding bands and pieces that will be worn regularly. here at NB Jewellers® we craft platinum jewellery with high quality platinum.
Platinum is normally marked with a PLAT, or “950pt.” if a ring contains 90% platinum it is hard and marked as 900pt, while if it is 50-90% it is marked PLAT and has no indicator of purity. Alloys which contain less than 50% of platinum is not marked based on FTC rules. The highest temperature for melting platinum is 950 parts platinum with 50 parts ruthenium, so it is hard to cast, while it is a darker grey than platinum mixed with iridium.
Setters recommend that this be used on diamond jewellery only, as diamonds require more pressure when they are being set. PT950/ru is extremely hard and as a result, more resistant to wear and tear over time.
PT 900 and 950/Ir are hard and medium alloys; one is hard and the other malleable. Both are white and soft, so they are both great with handmade jewellery. The softer the metal, the longer the polishing process, but they are both more scratch and bend resistant than alloys that are harder. They also hold the stones better in the event of an impact and are both resistant to wear and tear. Platinum mixed with 50 parts cobalt (PT950/Co), is also hard. It is great for making fine jewellery and also for filigree jewellery. Great craftsmanship is as critical in the process as the material, but there is no alloy for platinum is better than any other.
ALLOY AND METALS
We all take for granted the fact that we are able to purchase jewellery whenever we want, and the ability to choose the metal we would like on our rings. We seldom take thought of the metal that is used to make our rings as it is just there for us to choose. A lot of work goes into the manufacturing of Gold rings, as there are different alloys and different metals that are used in their manufacturing.
Alloys are metals that have been mixed with other elements to increase their strength and resist corrosion. Alloy is used because the properties that are found in metal are inadequate for some types of jobs. Iron can be a great material to use for building, but steel, (which is an alloy that is made with carbon and non-metallic material mixed together), is a harder, stronger and more rust-proof metal. Aluminium is light, but also soft in its purest form. Some of the metals that are usually used with gold as alloys to make jewellery are copper, iron, nickel, silver, tin, zinc, cadmium, titanium and manganese.
These alloys not only increase the strength of the gold, but also work in changing some other properties of gold. Some gold engagement rings cause a dark stain on the finger of the person wearing it and some cause allergic reactions, such as rashes and blisters. Because of the versatility of gold, it is very popular. Gold can be used to make many different shapes; if it is 18k or above, it will not get tarnished and will not cause irritation. White gold engagement rings, (or rings from gold that has been made with light materials and plated with rhodium), is a popular choice over a platinum engagement ring, because of its appearance and cost. It is categorised as platinum, and after silver, it is the whitest precious metal.
ADVANTAGES/DISADVANTAGES OF USING DIFFERENT GOLD ALLOYS FOR JEWELLERY:
18k Yellow Gold: Consists of 75% gold that is alloyed with silver, zinc, cobalt and copper, they have a richer look and feel than other metals used in the manufacturing of yellow gold rings. 18k gold is not plated, is very malleable, and will, in few circumstances, cause skin irritation. Some of the disadvantages are that unlike other jewellery that has a lower level purity alloy; it is less scratch-resistant. It also takes years to wear down, even with heavy wear.
18K White Gold: With white gold, which is also 75% gold with copper, palladium, zinc and nickel alloys, it is a whitish metal, which can be used in place of Platinum rings, if it has rhodium plating. White gold, or platinum rings, has a higher resistance than 18k yellow gold, to bending, or scratching. They possess high density and are very solid and can be very workable. On the other hand, for white gold, or platinum to have a high lustre, it will require rhodium plating. If the wearer has an allergy to nickel, then it will cause an irritation and takes a long time to wear down.
14K Yellow or White gold: Last, but not least, is the 14k yellow or white gold, which is the most popular of the four. 14k gold is stamped for identification purposes, possesses a mixture of 58% of the purest gold with a make-up of other metals, such as silver, nickel, copper, and zinc, amounting to 42% and is identified by the “14k” stamped on the link or lock. 14k gold requires no plating, is heavily resistant to bending or scratching and will not, in many cases, cause skin irritation. It is more cost effective that platinum alloys, or 18k gold, but is lighter than the 18k gold. It is more difficult to work with and is less resistant than its 18k counterpart.
METAL HARDNESS & STRENGTH
When it comes to precious metals, there is a distinct difference between their hardness and their strength. Hardness, or HV, is how scratch resistant the metal is when the surface is pierced with a pointed object that has load and gauging penetration. Hardness and scratch resistance are measured with the Vickers Hardness scale. Durability, or PSI, is measured by the pounds in each square inch and is tested when the tensile strength is measured for overall durability with pressure that could break the material.