PRECIOUS METALS
Katannuta jewellery is hand made in 18 carat gold, platinum or titanium, depending on a client's specifications and/or budget.
The purity of gold is expressed in carats (ct), not to be confused with the carat weight of gemstones. Pure gold is 24ct, but this is too soft for everyday use in jewellery. As a result, gold is alloyed with other metals to make it more durable and wearable. The type of alloy used will also affect the colour of the gold.
The caratage of the jewellery will tell you what purity the gold is:
* 9ct gold is 37.5% pure (mixed with 62.5% alloy)
* 18ct gold is 75% pure (mixed with 25% alloy)
9ct and 18ct gold are the standard gold purities used in South African and European manufactured jewellery. United States manufactured jewellery tends to be available in 10ct (42% pure) and 14ct (58% pure) gold.
Yellow gold is alloyed with silver and copper. It is the most frequently used type of gold there is. White gold is alloyed with a large percentage of silver, or a selection of other white metals. Alternatively, white gold may be produced by rhodium electroplating of gold. White gold is highly reflective and not subject to tarnish. The use of white gold predates the emergence of platinum into the jewellery market. Rose gold is alloyed with copper and sometimes silver. The proportions are about one part of copper to three parts of 24ct gold.
White gold is ideal for enhancing the white colour and brilliance of diamonds in the D - K colour categories, whereas yellow gold is better suited to diamonds with a slight yellow tint (K category onwards). There are no price differences between yellow and white gold, price is dependant only on the purity of the gold (i.e. 9ct or 18ct).
Despite being alloyed for greater durability, gold jewellery should still be carefully looked after. Try to avoid wearing your jewellery when doing rough work or handling chemicals and store jewellery items individually to prevent pieces scratching each other.
Platinum is growing in popularity in the jewellery industry. It is an exceptionally durable metal and its white lustre enhances the fire and brilliance of white diamonds much better than yellow gold. It is heavier than gold and this, combined with its more expensive market price (almost twice the price than gold, per ounce) makes it significantly more expensive than an equivalent gold piece of jewellery.
Platinum used in the manufacturing jewellery industry is alloyed with other heavy metals, palladium, rhodium, ruthenium, iridium and osmium. Today, platinum may also be alloyed with copper and titanium. It is the only precious metal used today in jewellery manufacturing that is 90% to 95% pure, largely hypoallergenic, and tarnish-resistant. Platinum purity is expressed as a factor of parts per thousand, where 95% pure platinum is marked as 950Pt. This refers to 950 parts platinum and 50 parts alloy metals. 900Pt contains 900 parts platinum and 100 parts alloy, and so forth.
Palladium is emerging as a viable alternative to platinum and white gold in the jewellery industry. It is a rare and lustrous silvery-white metal that is mined alongside platinum and, as it belongs to the same group of metals as platinum, it shares many physical and chemical similarities as platinum.
As palladium is a naturally white metal, it is a viable alternative to platinum and white gold in jewellery manufacture. Unlike white gold, palladium does not require rhodium-plating and, as it is not alloyed with other metals like nickel (as is the case with white gold), it will not tarnish over time. Because palladium rings are 95 – 100% pure palladium, they are hypo-allergenic and perfect for people with sensitive skin. Palladium is also harder than white gold so palladium jewellery is incredibly durable and is more suited to intricate designs than white gold.
One can’t ignore the fact that palladium is more cost effective than white gold and platinum. Palladium is currently 80% less than platinum and 70% cheaper than white gold. In addition, palladium is significantly lighter than platinum and as jewellery is often priced according to weight, a palladium ring will weigh much less than a platinum ring for an equivalent design.
Titanium has been widely used in commercial applications for a number of years and is now growing in popularity with regards to jewellery. More particularly, the men's titanium wedding ring market is growing in leaps and bounds, predominantly due to the fact that titanium's remarkable strength belies its light-weight feel. Titanium's strength is comparable to that of steel, while it is almost as light as aluminium.
Titanium is an inert metal, meaning that it is chemically inactive and does not react with other elements. The primary advantage of this characteristic is that titanium will never tarnish or discolour, as silver will. This inert character also means that titanium is a hypoallergenic metal and is thus ideal for people with sensitive skin. It is also resistant to salt-water and acid corrosion and is thus perfect for wear on a daily basis. Titanium will not cause irritation or discolouration of the skin.
Coloured titanium rings are becoming more popular in the market place. A wide range of colours can be produced by a process called anodizing whereby a layer of titanium dioxide is created. The resultant colour of the titanium dioxide depends on the voltage of the electrical current applied to the titanium. Unique titanium designs can be manufactured through the introduction of inlays into titanium bands. Katannuta offers titanium rings with inlays available in a choice of silver, gold or platinum.