Silver Purity Testing Methods for Loans: A Step-by-Step Look

The first thing that happens when silver reaches a lender's counter is a purity check, because everything that follows depends on that one reading. There are four silver purity testing methods that answer the question in practice, namely the acid test, X-ray fluorescence (XRF) scanning, electronic metal testers and the simple checks that can be done at home. The result matters because the fineness grade, whether 800, 925, 950 or 999, decides the net silver content on which a loan gets valued, and higher purity means more metal per gram, a higher assessed value and a larger eligible loan amount within the applicable limits. The sections below go through each of these methods, the colour readings behind the acid test, the fineness grades themselves, the Indian hallmark stamps, and the way all of this finally feeds into the loan calculation.

Four Main Methods Used to Test Silver Purity

The acid test is the traditional route and it is still widely used. A drop of nitric acid is placed on a small filed spot on the item, or on a streak drawn across a touchstone, and the colour reaction that follows is read by a trained eye against known grades. The method is quick and inexpensive, though it does leave a slight mark on the item, and what it gives is a band rather than an exact figure.

XRF scanning is the modern standard and the one professional lenders rely on for valuation, since the machine reads the elemental composition of the surface within seconds without touching or damaging the piece in any way. Electronic metal testers fall somewhere in between, being portable probes that estimate purity with moderate accuracy and serve well enough as a first screen. The home checks, which include the magnet test, the ice cube test and the sound of a tapped coin, can only separate obvious fakes from plausible silver, and grading the fineness is beyond what they can do.

Note: All figures are indicative. Actual amounts, fees, coverage percentages, and eligibility criteria may vary depending on the lender, borrower profile, loan category, and applicable guidelines at the time of application.

Acid Test: Nitric Acid Colour Reactions by Fineness Grade

The colour tells the story, though the readings do vary with the testing solution being used. With the silver testing solution commonly used in the trade, a bright red reaction is generally read as fine silver near 999, dark red as 925 sterling, and brown as 800-grade metal, while a green reaction points to a piece that is largely base metal. Plated items tend to give themselves away when the test is done on a filed notch, because the base metal under the thin silver layer reacts differently. Nitric acid is hazardous material, so this test belongs with a trained professional rather than at home, and even then the reading remains an approximation which the lender confirms by machine.

XRF Testing: Non-Destructive and the Lender's Preference

An XRF machine works by firing low-energy X-rays at the surface and reading the energy signature that comes back, which identifies each element present along with its proportion. The result appears within seconds, is accurate to within a fraction of a percent, and leaves no mark on the item. The one caution with XRF is that it reads the surface layer, which is incidentally also the reason it exposes plating, since a plated piece will not show the profile of solid silver. Under the RBI framework the borrower has the right to be present during the purity check, and the lender records the reading on a certificate that covers purity, gross and net weight, deductions and value.

Understanding Silver Fineness Grades: 800, 925, 950 and 999

Note: All figures are indicative. Actual amounts, fees, coverage percentages, and eligibility criteria may vary depending on the lender, borrower profile, loan category, and applicable guidelines at the time of application.

So which of these counts as pure silver, 999 or 925? Strictly speaking only 999 qualifies as fine silver, while 925 is sterling, an alloy hardened with copper. Between 925 and 950, sterling takes daily wear better whereas 950 suits delicate decorative work. And 800, which is the grade of a good deal of traditional Indian jewellery, is still genuine silver, only with a larger alloy share that brings down the net metal content per gram.

How Silver Purity Affects the Silver Loan Amount

The chain runs from purity to net content to value, and it works quite directly. A 100 gram item that tests at 999 contributes nearly the full 100 grams of fine silver to the valuation, whereas the same weight at 925 contributes 92.5 grams, and at 800 the contribution comes down to 80 grams. This net content is converted against the 99.9 fine benchmark and priced at the lower of the 30-day average and the previous day's closing price published by IBJA or a SEBI-recognised exchange, after which the loan-to-value ceiling applies as per the loan size, going up to 85%, 80% or 75% across the tiered slabs. Purity therefore moves the value base and not the percentage. Items that fail the lender's purity assessment, including silver-plated pieces, are declined as collateral. IIFL Finance may carry out purity testing through professional methods as part of its assessment of eligible silver, subject to applicable policies.

Common Signs of Fake Silver

• No hallmark, or a stamp that looks shallow, uneven or illegible
• Magnetic attraction; genuine silver is not magnetic
• A dull thud instead of a clear ring when the piece is tapped gently
• Ice melting no faster on the metal than on a table top; silver's high thermal conductivity melts it visibly quicker
• Green discolouration on the skin or the surface, a sign of high copper or base metal

Any one of these signs is grounds for doubt rather than proof in itself. A professional acid or XRF test is what settles the matter either way, and that is in any case the test a lender runs regardless of what the checks at home may have suggested.

Indian Hallmark Stamps: Reading BIS Marks on Silver

Silver hallmarking in India runs on IS 2112, which is the Bureau of Indian Standards specification for the metal. Under the HUID regime that was extended to silver from September 2025, a BIS-hallmarked silver item carries three marks, which are the BIS logo, the fineness number such as 925 or 999, and a six-digit alphanumeric HUID code. Lenders tend to look at the hallmark first because it is the quickest credible signal available, and then confirm through their own testing. The caution worth keeping in mind is that a bare 925 stamp by itself is only a seller's claim and not a certification, since anyone can strike three digits into soft metal, and it is the full set of BIS marks taken together that distinguishes a certified piece.

Conclusion

Purity testing is really the hinge on which every silver loan turns. The acid test gives a quick band, XRF gives the precise figure that lenders act on, and the home checks do no more than filter out obvious fakes. The tested fineness then sets the net silver content, the benchmark sets the price, and the tiered LTV slab sets the ceiling on what can be borrowed. IIFL Finance may offer a silver loan against eligible collateral, subject to product availability, borrower eligibility, collateral assessment and prevailing regulatory requirements. Valuation procedures, disclosures, and collateral handling are carried out in accordance with applicable policies and regulations.

Disclaimer : The information in this blog is for general purposes only and may change without notice. It does not constitute legal, tax, or financial advice. Readers should seek professional guidance and make decisions at their own discretion. IIFL Finance is not liable for any reliance on this content. Read more