ISO 19376-1:2025

Overview

ISO 19376-1:2025 - Jewellery and precious metals - Vocabulary - Part 1: Precious metals and units provides a standardized set of terms and definitions for the precious metals industry. Its purpose is to improve clarity across the supply chain - from refiners and assay laboratories to manufacturers, traders and consumers. The document covers core vocabulary for precious metals (including platinum group metals), units of measure, laboratory terminology, product and manufacturing terms, sampling and marking concepts. It explicitly excludes terms that apply only to jewellery and gemstones.

Key topics

The standard defines authoritative terminology and key technical measures used throughout the precious metals sector, including:

• Precious metals list: gold, silver, platinum, palladium, rhodium, iridium, ruthenium and osmium (PGMs).
• Fineness and minimums: definitions for fine precious metal, with minimum fineness examples (gold 995 ‰; silver and rhodium 999 ‰; platinum and palladium 999.5 ‰) and very high purity gold (≥ 999.99 ‰). Also sterling silver (925 ‰) and legal fineness concepts.
• Units: troy ounce (toz = 31.1034768 g), parts per thousand (‰), karat (K) for gold, and carat (ct) for gemstones (200 mg).
• Assay and laboratory terms: assay, touchstone testing and acids, cupellation (fire assay), proof sample, reference material (RM) and certified reference material (CRM), bracketing technique, internal standard.
• Products and bars: doré, cast and minted bars, kilobar, bullion, good-delivery bars, and distinctions between counterfeited and fake bars.
• Manufacturing & processing: casting methods (lost-wax, continuous), refining, electroforming, additive manufacturing, metal forming, soldering/brazing, pickling and etching.
• Marking and sampling: definitions for marking, fineness marking, and negative tolerance (allowed deviation below marked fineness).

Applications and users

ISO 19376-1:2025 is practical for:

• Refiners, assayers and analytical laboratories for consistent reporting and method communication.
• Bullion producers, mints and metal traders for clear product descriptions (kilobar, bullion, good-delivery).
• Quality managers and compliance teams involved in hallmarking, customs, and legal fineness verification.
• Manufacturers and process engineers using standard terminology for casting, refining, electroforming and additive manufacturing.
• Regulators, standards bodies and consumer-facing information where harmonized vocabulary reduces disputes and improves transparency.

Related standards

Standards cited or aligned with ISO 19376-1:2025 include (examples):

• ISO 9202 - commonly recognized finenesses;
• ISO 11426 - cupellation (fire assay) method;
• ISO 24018 - kilobar requirements;
• ISO 17034 - reference material / CRM principles;
• ISO 8654, ISO/TS 6084, ISO/TS 20593 - related terms and analytical practices.

Using ISO 19376-1:2025 supports consistent terminology for precious metals, improving trade clarity, assay accuracy and regulatory compliance.