If you are comparing silver nursing cups, you may have noticed two numbers appearing again and again: 925 and 999. They describe the purity of the silver, but they do not tell you everything about how a pair of cups will feel, fit or work in day-to-day breastfeeding.
Here is the simple difference: 925 silver contains 92.5% silver, while 999 silver contains 99.9% silver. Both are recognised silver standards. The better choice for you also depends on the shape, depth, weight, finish and care instructions of the cups.
What does 925 silver mean?
925 silver is commonly called sterling silver. It contains 92.5% silver, with the remaining 7.5% made up of other metals that help create the finished alloy.
Sterling silver is widely used in jewellery and many silver nursing cups. The exact composition of the remaining metal can vary, so it is worth checking the product information if you have known metal sensitivities.
What does 999 silver mean?
999 silver is 99.9% silver and is often described as fine silver. It contains less alloying material than 925 silver.
Lactivate Silver Nursing Cups are made from 999 silver. Each cup contains approximately 4 g of silver and is shaped to sit over the nipple between feeds. The one-size cups measure approximately 5.5 cm in diameter with an internal depth of 1.8 cm and include removable silicone comfort rings.
Does a higher silver number automatically mean a better cup?
Not on its own. Purity is easy to compare, but comfort is more personal. A cup can be made from high-purity silver and still be the wrong shape or depth for your body. Likewise, a well-designed 925 silver cup may suit one mum better than another design made from 999 silver.
Look at the complete product rather than relying on one number. Useful details include the silver purity, amount of silver, diameter, internal depth, edge finish, whether a comfort ring is included and the brand's cleaning and care guidance. You can also learn more about what silver nursing cups are and how they work.
Why did Lactivate choose 999 silver?
We chose 999 silver so the material is simple and clearly understood: 99.9% silver. We also wanted a substantial cup with approximately 4 g of silver in each side, rather than focusing on purity while overlooking the amount of material used.
The smooth one-size shape is designed to provide space around the nipple, while the removable silicone rings give mums the option of a softer edge against the breast. As with every breast-care product, comfort and suitability vary from person to person.
What should you compare before buying?
Start with the measurements. Check that the diameter will cover the nipple comfortably without pressing into surrounding breast tissue, and consider whether the internal depth gives your nipple enough room without rubbing.
Then compare what is included, how the cups are cleaned, whether the brand clearly identifies the silver standard and whether local customer support is available. If a product makes therapeutic claims, check the information supplied with it and its Australian regulatory status rather than relying only on marketplace descriptions.
The bottom line
925 means 92.5% silver and 999 means 99.9% silver. That difference matters, but it is only one part of choosing silver nursing cups. Purity, weight, dimensions, shape, finish and comfort all belong in the comparison.
If you would like to see the full specifications, view the Lactivate Silver Nursing Cups or read our complete guide to silver nursing cups.
Frequently asked questions
Is 999 silver the same as pure silver?
999 silver is 99.9% silver and is commonly described as fine or pure silver. No commercially described 999 silver product is literally 100.0% silver.
Is sterling silver the same as 925 silver?
Yes. Sterling silver contains 92.5% silver and is marked 925.
Is 999 silver always softer than 925 silver?
Fine silver is generally more malleable than sterling silver. The finished cup's thickness, forming and design also affect how it feels and holds its shape.
What matters besides silver purity?
Check the weight of silver, cup diameter and depth, finish, included accessories, care instructions and whether the design feels comfortable for your body.
