Feb 2024


Feb 2024

The Fineness and Purity Of Silver Explained

By StoneX Bullion

Silver is an extremely malleable metal. In its purest form, it’s softer than both platinum and gold. Because of this pliability, silver is alloyed with other metals - typically copper - to increase its durability and strength.

Fineness and purity are two measures that allow investors to understand how much silver content is in any given item. Silver purity is simple and refers to the percentage of pure silver. A silver bar with 99.9% purity is as close as you can get to pure silver. Fineness expresses silver purity in parts of one thousand. For example, a silver bar with a purity of 99.9% will be labeled as having 999 fineness.

Before you start investing in silver, taking the time to familiarize yourself with these concepts can guide you to make the best investment decisions. In this guide, we’ll explain silver purity and fineness and offer some advice for investors.

What is silver purity?

Silver purity is the amount of pure silver contained within a silver alloy. It’s typically expressed as a percentage. For example, a silver coin with 995 purity contains 99.5% silver and 0.5% another metal, such as copper.

What is silver fineness?

Silver fineness measures the exact ratio of pure silver versus alloy metals in parts per thousand. It’s also known as millesimal fineness. For example, sterling silver has a minimum purity of 92.5% silver with the remaining 7.5% made up of another alloy. In fineness, this would be displayed as 925, meaning that 925 out of 1000 parts of the alloy are made from pure silver.

Sometimes, millesimal fineness is displayed as a decimal. In this case, a 999 silver coin would be displayed as having .999 fineness.

What are silver hallmarks?

Silver bullion and jewelry are imprinted with hallmarks that indicate their millesimal fineness. This stamp allows investors to quickly determine the amount of actual silver in their investment and gauge its value. For example, this 2021 Australian Koala silver coin is hallmarked with 999 silver so investors can easily gauge its value and purity at a glance.

Most common silver fineness denominations

Below are some common fineness denominations you’ll find when buying silver.






Fine or pure silver



Brittania silver



Sterling silver



Coin silver



Jewelry silver

Let’s look at these purity levels in more detail:

  • 999 - This is the purest silver you can buy. Because 100% pure silver is too malleable to be handled properly, 999 is as close as you can get to the real thing. 999 silver is also called fine silver and is used for trading bullion.
  • 958 - Britannia silver is a common standard in Britain, made from 95.8% pure silver. Be sure not to confuse Britannia silver with the similarly named Silver Britannia coins.
  • 925 - This is one of the most popular silver fineness denominations, also known as sterling silver. It’s commonly used for jewelry making and decorative items.
  • 900 - Also known as coin silver, silver with 900 fineness is often used to mint coins for general circulation (as opposed to silver investment coins).
  • 800 - Silver with an 800 fineness contains 20% alloy metals. It’s often used to create jewelry that’s lower quality than sterling silver.

What is considered fine silver?

Fine silver, also called pure silver, is a term that refers to the highest purity silver available, which is 99.9% purity or 999 fineness (sometimes called ‘three nines fine’). Only silver with 999 fineness can be traded on the metal and commodities exchanges, including investment-grade silver bars and coins. These will always be stamped with a hallmark denoting their purity.

At StoneX Bullion, we only sell fine silver of 99.9% purity and above. Many of our investment-grade silver bars and coins have a fineness of 9999, such as the 1oz Somalia Elephant Silver Coin.

What is fine silver used for?

Because of its high purity, fine silver is only used for bullion investments as it’s far too malleable for industrial, commercial, or jewelry uses. The most common types of silver bullion investments are silver bars (also known as ingots) and silver coins.

Investment-grade silver bars

Pure silver bars are the most common way to invest in large amounts of physical silver. They are available in numerous sizes for all investment types, from 1oz to 10oz and up to 100oz (the most popular size). Smaller units, like 1oz, are typically minted while silver bars weighing 100g and more are simply cast. Be aware that an oz in the precious metals world refers to a troy ounce and not a standard ounce.

Read more: Troy Ounce: Definition, History, and Conversion Table

Investment-grade silver coins

Silver coins are more popular for smaller investments and tend to command a higher premium over the silver spot price. Unlike silver bars, coins have added value due to their unique collectible nature. Silver coins are released by particular mints and issued in limited quantities, contributing to their numismatic value.

You can find a signature silver coin from many of the world’s largest mints. For example, the Perth Mint releases the Australian Kangaroo Coin, the Royal Canadian Mint has its iconic Silver Maple Leaf, the Austrian Mint has its Vienna Philharmonic Silver Coin, and the Rand Refinery South Africa is known for its Silver Krugerrand Coin.

Sometimes these silver coins can be used as legal tender, depending on the country. Silver coins in general circulation aren’t made from fine silver and do not carry the same value as silver bullion coins. However, they can still be useful investments from a collectible point of view.

See more: Pros and Cons of Buying Gold Bars vs Gold Coins

Why is fine silver used in bullion?

So, why is it that only fine silver can be used for bullion bars and coins? To understand that, we should dive a bit deeper into the silver bullion market and talk about the London Bullion Market Association (LBMA).

The LBMA is an international trade association that represents the global bullion market, setting standards that govern how silver and other precious metals are refined and traded. These standards are known as ‘Good Delivery’ and outline everything from the size, weight, markings, and fineness for bullion bars and coins sold on the precious metals exchange. According to Good Delivery, silver bullion bars must be at least 999 fineness.

As an affiliate of the LBMA, all of StoneX Bullion’s silver bars are in line with Good Delivery standards and at least 99.9% purity. (See: How to Tell the Difference Between Real and Fake Silver).

Variations in global silver purity standards

To add an extra layer of complexity, there are some variations in global standards of silver fineness and purity. Let’s take a look at some of these differences…

  • Like most places, sterling silver in the UK must have at least 925 fineness. However, what’s unique is that sterling silver in the UK is stamped with a lion passant mark. You’ll see this on silver cutlery and coins to denote purity.
  • In some parts of Asia, the standard for high quality silver is generally a 950 fineness (the same as sterling silver elsewhere).
  • In Mexico, silver jewelry tends to be of higher quality than traditional sterling silver. Here, 970 or 980 fineness can be the norm.
  • Coins and silverware from the Middle East tends to sit at the lower end of fineness with 935 or 900 common purity grades.

While you don’t necessarily need to remember all these differences, it can be helpful for silver investors and collectors to understand silver purity standards from around the world, especially when reading hallmarks.

How to care for silver

Depending on its purity and fineness, silver will need to be protected, cleaned, and maintained in different ways. Below, we outline some general guidelines for different silver purity levels:

  • Fine silver: Pure silver of 999 fineness, such as silver coins and bars, is soft and can easily be scratched. When cleaning, use gentle polishing cloths and avoid any abrasive cleaners. Store away from other metals to prevent tarnishing.
  • Sterling silver: Silver with a fineness of 950 can be cleaned with a silver polishing cloth. If tarnished, it can be immersed in a silver cleaning solution and dried. Avoid wearing sterling silver jewelry in chlorinated water as it can cause damage.
  • Coins silver: This grade of silver has 900 fineness and is sensitive to sulfur-based environments. When handling, wear gloves and use specialized archival supplies to protect your collectible silver coins.
  • Silver-plated: Silver plated items are made from a base metal with a very thin layer of fine silver coating. Because it’s so thin, this silver layer is very sensitive. Avoid scrubbing and using silver polish as it can remove this layer. Gently clean with mildly soapy water.

Silver purity FAQs

Still have a few questions on your mind? Below, we answer some of the most common questions around silver purity and fineness.

Can silver be 100% pure?

You cannot buy 100% pure silver as the metal is too soft and malleable to be used in jewelry, coins, bars, or products. Generally, the purest form of silver you'll find is 99.9%, though you can buy silver bullion with 99.99% purity such as the 1oz Silver Maple Leaf Coin or 500g Silver Bar from Nadir Metal Rafineri.

Is 925 silver good quality?

Yes, 925 silver is also known as sterling silver and is good quality silver for jewelry and other decorative items. For investments, it’s best to look at 999 silver and above.

What is nickel silver?

Also known as German silver or alpaca silver, nickel silver is a copper alloy with nickel and zinc. This gives the look of silver but does not contain any actual silver. It's generally considered a cheap and durable substitute for silver.

What is the purity of silver?

Silver purity is a percentage of actual silver versus other metals in an alloy. Because silver is so soft and malleable, it’s often alloyed with metals such as copper. Purity denotes how much silver is in an item. For example, 90% purity means there is 10% of other metals.

How can you tell if silver is real or fake?

There are many ways you can spot fake silver. The first thing to do is check for stamps and purity hallmarks. If you’re unsure, you can try some home tests for silver authenticity, like the ice cube test or ping test. Finally, a professional will always be able to determine the true value of your silver products.

Should I invest in gold or silver?

Both silver and gold make valuable investments and have been shown to retain their value over time. We recommend reading this article to understand the differences between the two precious metals: Gold vs Silver Investments: Which is Better?

Is .999 silver the same as fine silver?

Yes, .999 silver (sometimes written as 999 silver) is known as fine silver and is the standard for investment-grade bullion bars and coins.

What are the fineness marks on silver?

Fineness marks on silver coins, bars, jewelry, and decorative items are a display of purity. A fineness mark of 925, for example, shows that the item is made from sterling silver. A fineness of 900 means the item is 90% pure silver and 10% other metals. Fineness marks are a reliable way to tell the value of your silver items.

Invest in silver bars and coins

Start investing in the highest purity silver coins and bars available on the market. StoneX Bullion is one of the biggest precious metal dealers in the UK and Europe, with an extensive range of silver bars and rare coins from the world’s best mints.

We also stock other high-quality and sought-after metals, such as pure gold coins, platinum, and palladium bars and coins. Browse our investment-grade silver and precious metals and start building your investment portfolio today.