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What is 999 platinum?

Understand Your Investment: What is 999 Platinum?

Although not as commonly spoken about as gold, platinum holds a great deal of influence within the jewellery world.

Since its emergence on the mass-consumption jewellery scene in the 1920s, platinum gained immediate popularity, primarily due to its strength and resistance to tarnishing and discolouration. It’s widespread knowledge that 24-karat gold is the highest-quality gold available on the market, which leaves us with the question: what is the purest platinum?

The purity in most fine platinum jewellery is 95-99%, typically in an alloy with rhodium and silver. Platinum holds the advantage of being more durable than gold and is also the heaviest of precious metals.

Platinum is also around 50% denser than gold, which results in it costing more than gold in equal-sized pieces of jewellery. This is simply because platinum weighs so much more than gold of the same volume.

Platinum’s journey to the top

Once only available and mined in Colombia, platinum mining began to spread around the globe after it was discovered in Russia’s Ural Mountains in 1819. From here, Canada started to unearth the precious metal in 1888, which helped the country become the biggest exporter of the metal after World War I.

Following the discovery of platinum in South Africa in 1924, however, South Africa became – and continues to be – the largest exporter of platinum in the world. A whopping 75% of the world’s newly mined platinum comes from South Africa.

Formerly used solely for decoration and laboratory equipment, platinum was first used in jewellery in the late 1800s. The celebrated jeweller Cartier and his sons were the pioneers of platinum, which created a high demand for platinum among the world’s royal families.

Following platinum’s further acclaim throughout the 1920s and 1930s, white gold also gained a popularity boost due to its similar appearance. Although vastly different metals, it is almost impossible to tell platinum apart from white gold at a glance.

At the end of the day, the best way to think about 999 platinum is to consider it as the platinum equivalent to 24-karat gold; the highest possible grade that the metal can be. Now that we’ve got our heads around exactly what 999 platinum is, let’s take a look at how we can recognise whether or not it has been used within jewellery.

Simple Platinum Hallmark Guide

Platinum hallmarking was first introduced in the UK in 1975 as a result of legislation brought about by the Hallmarking Act of 1973.

Prior to this, platinum items would often carry no markings, or simply ‘Plat' or ‘Platinum', and would be of varying purity. This means that before 1975, there was no definitive way of knowing whether or not an acquired piece of platinum jewellery was completely pure.

Today in the UK, all platinum items weighing over 0.50 grams must be stamped with a hallmark that certifies the metal's purity. The grading for platinum purity begins at the top with 999 platinum, and makes its way down from there. Below are some of the most popular platinum purities used around the world:

900 platinum contains 90% of pure platinum (the stamp for this is 900) 950 platinum contains 95% of pure platinum (the stamp for this is 950) 999 platinum contains 99% of pure platinum (the stamp for this is 999)

There are of course other different purities used outside of these three, with the figure for recognised commercial platinum sliding down to as low as 850. There are also a few endearing nicknames for some of the purities of platinum, which include “three nines fine” for 999 platinum and “one nine fine” for 900 platinum.

What does this mean for 999 platinum?

As mentioned, 999 platinum is the highest purity of platinum. It is, in fact, so pure that it's sometimes referred to as ‘five nines' (99.999%) pure. As you would expect, platinum 999 is also the most expensive type of platinum, and is often used in the production of high-end jewellery and investment-grade bullion bars and coins.

One of the leading benefits of a platinum piece being 999 pure is that investors or buyers know that the item is worth its exact weight in whatever the current market value for platinum is at a given time.

To ascertain if an item is genuinely made of platinum, and is 99.9% pure, you can check for some simple markings on your jewellery. We will discuss these in more detail below.

The three compulsory platinum marks

Say you’ve just purchased a brand-new 999 platinum ring, and you’re curious as to how legitimate the quality of the ring is. Thankfully, a few compulsory platinum marks exist, which can help you find out exactly how pure your item of jewellery is.

Provided your item of platinum jewellery weighs more than 0.50 grams, it should always contain these three marks:

Sponsor Mark

Also referred to as the Maker’s Mark, the first stamp in the photo indicates who submitted the item for hallmarking.

Each sponsor (maker) has its own unique stamp, which will come in the form of initials encircled by a shield design. This shield design plays a particularly important role, as many different sponsors may have the same initials.

Assay Office Mark

The assay office mark tells you which assay office tested and hallmarked your item.

This mark proves as evidence that an assay office has determined that your piece qualifies for an appropriate hallmark.

Fineness Mark

The third stamp in our example photo is the fineness mark. This tells you the precious metal content, expressed in parts per thousand. There are four recognised standards of platinum:

850 (85% pure) 900 (90% pure) 950 (95% pure) 999 (99.9% pure)

When identifying an item as being platinum, it's important to check the shape and contents of the fineness mark. If the shape is anything other than what is shown below, it simply isn't platinum.

Provided your jewellery item comes complete with these three marks, you’ve got the real deal!

Optional platinum hallmarks

The following three marks are all optional. Under hallmarking legislation, there is no compulsory requirement to show these additional marks. However, they are often still displayed on items of platinum jewellery.

These additional marks are as follows:

Traditional Fineness Symbol

If your platinum item has a purity of 950 or 999, it may display the traditional orb mark. In our example photograph, you can see the second stamp is the traditional fineness symbol.

Date Letter

Date letters are optional and, therefore, not always seen (as in our example photograph).

The date letter tells us the year the item was hallmarked. As date letters were standardised across all assay offices from 1975, it's quite easy to read. Below is a chart of all date letters from 1975 onwards.

International Convention Mark

An International Convention Mark is sometimes shown within the hallmark.

It is a mark recognised by all member countries of the International Hallmarking Convention.

Testing your 999 platinum jewellery

Without a valid hallmark, most jewellers and small-scale gold buyers will be unable to ascertain platinum jewellery's purity accurately.

Due to its inherent inertness, traditional ‘acid' testing can only help determine if an item isn't platinum, which means you couldn’t, for example, differentiate 900 and 999 platinum. This could result in you knowing whether or not your item of jewellery is platinum, but not knowing if it is pure platinum.

Another simple test which you can conduct at home is the magnet test. Because platinum is not magnetic, if your jewellery item responds to a magnet with a magnetic pull, you’ll know that the item is not pure platinum. In this instance, there’s a good chance the piece is white gold alloyed with nickel instead.

If you’ve established that your jewellery is platinum, but you want to know exactly how pure it is, it’s best to take the piece to a professional for assessment. High-end and specialist precious-metal dealers use XRF (X-ray fluorescence) testing to identify the exact platinum content of jewellery accurately. Inductively coupled plasma and optical emission spectrometry are also common techniques used by assay offices throughout the hallmarking process.

Now that you’ve got a better understanding of what platinum is, and more specifically, how the purity system of platinum works, you’re just about ready to invest in this celebrated and precious metal.

When it comes to platinum jewellery, you need look no further than 7879’s exclusive and distinguished 999 Platinum collection.

Purchasing 999 platinum jewellery provides you with a modern and chic way to invest your money. Platinum jewellery’s uniqueness is bound to set you apart when you wear it out for the world to see.

Through 7879’s bespoke 999 platinum pieces, you can invest your money in tasteful and timeless jewellery items that will maintain their value for many years.

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