Reference guide · Glossary
Precious Metals Industry Glossary
Plain-language definitions for assaying, bullion, doré, cupellation, fineness, karat, LBMA, traceability, refining, XRF, ICP, and related terms.
What this guide establishes
- Technical terms should remain connected to sample, method, units, and context.
- Commercial labels such as bullion or 24 karat are not substitutes for verification.
- Traceability, custody, testing, and responsible sourcing answer related but different questions.
Precious-metals transactions use technical, commercial, compliance, and logistics language. A familiar word can mean something narrower in a laboratory report than it does in a sales conversation. This glossary explains the terms a buyer, exporter, miner, refiner, investor, or public officer is most likely to encounter and shows what each term does and does not establish.
Assay
An assay is a controlled analytical determination of one or more components in a submitted sample. In gold work, it commonly reports gold content using a stated method and unit.
Buyers, miners, refiners, and exporters use assays for verification, process control, valuation inputs, or settlement discussions.
When this term appears in a report, contract, invoice, or discussion, ask which material, method, unit, organisation, or process it refers to. Record that definition in the transaction file so every party uses the word consistently.
The strongest support comes from the underlying records rather than the label itself. Match the term to sample references, laboratory documents, product specifications, custody records, or official sources as appropriate.
The result normally represents the tested sample and should not be expanded to an unsampled lot.
Bullion
Bullion is precious metal valued mainly by weight and purity rather than artistic or face value. It may be produced as bars, ingots, wafers, or recognised investment products.
Product specifications, producer identity, serial records, weight, fineness, and market requirements affect acceptance.
When this term appears in a report, contract, invoice, or discussion, ask which material, method, unit, organisation, or process it refers to. Record that definition in the transaction file so every party uses the word consistently.
The strongest support comes from the underlying records rather than the label itself. Match the term to sample references, laboratory documents, product specifications, custody records, or official sources as appropriate.
A bar shape or stamp does not prove that an item is genuine bullion.
Doré
Doré is an intermediate, partly refined alloy containing gold with silver and other metals. It is commonly produced before final refinery separation and upgrading.
Doré normally requires representative sampling and assay for commercial evaluation and refining.
When this term appears in a report, contract, invoice, or discussion, ask which material, method, unit, organisation, or process it refers to. Record that definition in the transaction file so every party uses the word consistently.
The strongest support comes from the underlying records rather than the label itself. Match the term to sample references, laboratory documents, product specifications, custody records, or official sources as appropriate.
Doré may be heterogeneous and should not be described as refined high-purity bullion without evidence.
Cupellation
Cupellation is a high-temperature separation stage used in Fire Assay. Lead and other base components are oxidised and absorbed, leaving a small precious-metal bead for further treatment and measurement.
The step helps isolate precious metals from the fused test portion.
When this term appears in a report, contract, invoice, or discussion, ask which material, method, unit, organisation, or process it refers to. Record that definition in the transaction file so every party uses the word consistently.
The strongest support comes from the underlying records rather than the label itself. Match the term to sample references, laboratory documents, product specifications, custody records, or official sources as appropriate.
Correct furnace conditions, cupels, controls, and skilled observation are essential.
Fineness
Fineness expresses precious-metal content in parts per thousand. Gold reported at 999 fineness contains approximately 999 parts gold per 1,000 on the stated analytical basis.
Fineness provides a precise language for bullion specifications and settlement calculations.
When this term appears in a report, contract, invoice, or discussion, ask which material, method, unit, organisation, or process it refers to. Record that definition in the transaction file so every party uses the word consistently.
The strongest support comes from the underlying records rather than the label itself. Match the term to sample references, laboratory documents, product specifications, custody records, or official sources as appropriate.
A fineness stamp is a claim until it is connected to verified material and testing.
Karat
Karat describes gold purity using 24 parts. Eighteen karat is nominally 18 parts gold in 24, which corresponds to approximately 750 fineness.
Karat is common in jewellery descriptions and consumer marking.
When this term appears in a report, contract, invoice, or discussion, ask which material, method, unit, organisation, or process it refers to. Record that definition in the transaction file so every party uses the word consistently.
The strongest support comes from the underlying records rather than the label itself. Match the term to sample references, laboratory documents, product specifications, custody records, or official sources as appropriate.
Nominal karat does not replace an actual assay where precise composition matters.
LBMA
LBMA stands for the London Bullion Market Association. It publishes market standards and operates the Good Delivery system for refiners meeting its requirements.
Buyers may refer to LBMA standards, responsible sourcing guidance, or listed refiners in acceptance criteria.
When this term appears in a report, contract, invoice, or discussion, ask which material, method, unit, organisation, or process it refers to. Record that definition in the transaction file so every party uses the word consistently.
The strongest support comes from the underlying records rather than the label itself. Match the term to sample references, laboratory documents, product specifications, custody records, or official sources as appropriate.
Using the letters LBMA does not make a bar, laboratory, trader, or transaction accredited.
Traceability
Traceability is the ability to follow material and related information through stages of production, purchase, transport, processing, and sale.
Lot IDs, weights, invoices, transport records, source records, and reconciliations support traceability.
When this term appears in a report, contract, invoice, or discussion, ask which material, method, unit, organisation, or process it refers to. Record that definition in the transaction file so every party uses the word consistently.
The strongest support comes from the underlying records rather than the label itself. Match the term to sample references, laboratory documents, product specifications, custody records, or official sources as appropriate.
Traceability is an input to due diligence and does not prove that every activity was responsible.
Chain of custody
Chain of custody is the documented sequence showing who controlled a material or sample, when transfers occurred, and how identity was protected.
Seals, signatures, photographs, timestamps, storage records, and transfer logs support custody.
When this term appears in a report, contract, invoice, or discussion, ask which material, method, unit, organisation, or process it refers to. Record that definition in the transaction file so every party uses the word consistently.
The strongest support comes from the underlying records rather than the label itself. Match the term to sample references, laboratory documents, product specifications, custody records, or official sources as appropriate.
Custody shows control, not legal ownership.
Smelting
Smelting uses heat and chemical processes to separate or concentrate metal from ore, concentrate, or other material. It may produce a metal-rich intermediate such as doré.
Smelting changes material form and can require weight, process, and batch reconciliation.
When this term appears in a report, contract, invoice, or discussion, ask which material, method, unit, organisation, or process it refers to. Record that definition in the transaction file so every party uses the word consistently.
The strongest support comes from the underlying records rather than the label itself. Match the term to sample references, laboratory documents, product specifications, custody records, or official sources as appropriate.
Smelting is not the same as final refining to a high-purity product.
Refining
Refining removes remaining impurities and separates precious metals to reach a target product specification. Methods depend on feed material and desired output.
Refineries use assay and process control to calculate feed, recovery, product, and settlement.
When this term appears in a report, contract, invoice, or discussion, ask which material, method, unit, organisation, or process it refers to. Record that definition in the transaction file so every party uses the word consistently.
The strongest support comes from the underlying records rather than the label itself. Match the term to sample references, laboratory documents, product specifications, custody records, or official sources as appropriate.
A refinery document should be verified and linked to the actual lot or bar.
XRF
XRF means X-ray fluorescence. The technique measures characteristic X-rays emitted by elements in the surface region of a sample.
It is useful for rapid, non-destructive elemental screening and comparison of several points.
When this term appears in a report, contract, invoice, or discussion, ask which material, method, unit, organisation, or process it refers to. Record that definition in the transaction file so every party uses the word consistently.
The strongest support comes from the underlying records rather than the label itself. Match the term to sample references, laboratory documents, product specifications, custody records, or official sources as appropriate.
Surface condition, plating, calibration, and non-uniform interiors can affect interpretation.
ICP
ICP refers to inductively coupled plasma techniques such as ICP-OES or ICP-MS, which measure elements in a prepared solution using a high-temperature plasma.
ICP methods can support multi-element analysis and low-level measurements after suitable sample digestion or preparation.
When this term appears in a report, contract, invoice, or discussion, ask which material, method, unit, organisation, or process it refers to. Record that definition in the transaction file so every party uses the word consistently.
The strongest support comes from the underlying records rather than the label itself. Match the term to sample references, laboratory documents, product specifications, custody records, or official sources as appropriate.
Results depend on complete preparation, calibration, interference control, and the specific validated method.
Fire Assay
Fire Assay is a laboratory process that uses fusion, collection, cupellation, and a stated finish to determine precious metals in a weighed prepared sample.
It is widely used for representative gold determination where accuracy matters.
When this term appears in a report, contract, invoice, or discussion, ask which material, method, unit, organisation, or process it refers to. Record that definition in the transaction file so every party uses the word consistently.
The strongest support comes from the underlying records rather than the label itself. Match the term to sample references, laboratory documents, product specifications, custody records, or official sources as appropriate.
The method consumes material and depends on representative sampling and quality control.
Flux
Flux is a selected mixture added during Fire Assay fusion to help control melting, slag formation, oxidation or reduction, and collection of precious metals.
The recipe is adjusted to the sample matrix and analytical objective.
When this term appears in a report, contract, invoice, or discussion, ask which material, method, unit, organisation, or process it refers to. Record that definition in the transaction file so every party uses the word consistently.
The strongest support comes from the underlying records rather than the label itself. Match the term to sample references, laboratory documents, product specifications, custody records, or official sources as appropriate.
Incorrect flux balance can affect fusion quality and recovery.
Assay report
An assay report is the controlled document stating laboratory findings for an identified sample using a stated method and units.
It supports technical review, transaction reconciliation, refining, or compliance files when connected to custody.
When this term appears in a report, contract, invoice, or discussion, ask which material, method, unit, organisation, or process it refers to. Record that definition in the transaction file so every party uses the word consistently.
The strongest support comes from the underlying records rather than the label itself. Match the term to sample references, laboratory documents, product specifications, custody records, or official sources as appropriate.
It does not by itself prove ownership, origin, export approval, or transaction legitimacy.
Clear answers before the next step.
What Is Bullion?
Bullion is precious metal valued mainly by weight and purity and produced to a defined product specification. Check producer, identity, weight, purity, and buyer acceptance. A bar shape does not prove genuine bullion. The appropriate response depends on the material, jurisdiction, parties, value, and intended use, so buyers, exporters, miners, refiners, investors, manufacturers, and public officers should confirm transaction-specific requirements before acting.
What Is Doré Gold?
Doré is a partly refined alloy containing gold with silver and other metals. Use representative assay before commercial settlement or refining. Appearance does not establish purity. The appropriate response depends on the material, jurisdiction, parties, value, and intended use, so buyers, exporters, miners, refiners, investors, manufacturers, and public officers should confirm transaction-specific requirements before acting.
What Is Cupellation?
Cupellation heats the lead collector under controlled conditions so base components oxidise and a precious-metal bead remains. Review it as one controlled stage within the full Fire Assay method. Poor conditions can affect the analytical result. The appropriate response depends on the material, jurisdiction, parties, value, and intended use, so buyers, exporters, miners, refiners, investors, manufacturers, and public officers should confirm transaction-specific requirements before acting.
What Is Gold Fineness?
Gold fineness states the gold proportion in 1,000 parts of material. Use the stated assay value and units in commercial calculations. A stamp is not independent proof. The appropriate response depends on the material, jurisdiction, parties, value, and intended use, so buyers, exporters, miners, refiners, investors, manufacturers, and public officers should confirm transaction-specific requirements before acting.
What Is the Difference Between Smelting and Refining?
Smelting separates or concentrates metal using heat, while refining removes remaining impurities and separates metals to reach a target product. Describe the actual process and product accurately. An unfinished smelted bar should not be called refined bullion. The appropriate response depends on the material, jurisdiction, parties, value, and intended use, so buyers, exporters, miners, refiners, investors, manufacturers, and public officers should confirm transaction-specific requirements before acting.
What Does LBMA Mean?
LBMA is the London Bullion Market Association, which publishes standards and operates the Good Delivery system. Verify any claimed listing or status through official LBMA information. The acronym is often misused and does not accredit every gold business. The appropriate response depends on the material, jurisdiction, parties, value, and intended use, so buyers, exporters, miners, refiners, investors, manufacturers, and public officers should confirm transaction-specific requirements before acting.
What Is Traceability?
Traceability connects material identity and records across production, purchase, transport, processing, and sale. Reconcile quantities, dates, parties, and movements. Traceable does not automatically mean responsible or lawful. The appropriate response depends on the material, jurisdiction, parties, value, and intended use, so buyers, exporters, miners, refiners, investors, manufacturers, and public officers should confirm transaction-specific requirements before acting.
What Is ICP Analysis?
ICP-OES and ICP-MS measure elements in prepared solutions using an inductively coupled plasma and optical or mass detection. Confirm the preparation, analytes, reporting limits, and validated method. Incomplete digestion or interference can affect results. The appropriate response depends on the material, jurisdiction, parties, value, and intended use, so buyers, exporters, miners, refiners, investors, manufacturers, and public officers should confirm transaction-specific requirements before acting.
Is doré the same as bullion?
Doré is usually an intermediate alloy before final refining, while bullion generally refers to precious metal valued by weight and purity under a product specification. Describe and test the actual material. Bar shape alone does not determine the category. The appropriate response depends on the material, jurisdiction, parties, value, and intended use, so buyers, exporters, miners, refiners, investors, manufacturers, and public officers should confirm transaction-specific requirements before acting.
Is fineness the same as karat?
Both express gold proportion, but fineness uses parts per thousand and karat uses 24 parts. Use fineness for precise commercial comparison. Nominal conversions do not replace a measured result. The appropriate response depends on the material, jurisdiction, parties, value, and intended use, so buyers, exporters, miners, refiners, investors, manufacturers, and public officers should confirm transaction-specific requirements before acting.
Does LBMA certify all gold laboratories?
No. LBMA operates specific programmes and the Good Delivery system. Claims should be checked against official LBMA information. Verify the exact organisation and status claimed. The term should not be used as a generic quality badge. The appropriate response depends on the material, jurisdiction, parties, value, and intended use, so buyers, exporters, miners, refiners, investors, manufacturers, and public officers should confirm transaction-specific requirements before acting.
Is XRF the same as Fire Assay?
No. XRF is a rapid elemental surface-region technique. Fire Assay analyses a prepared sample through fusion and cupellation. Choose from the question and material. The results may not describe the same portion. The appropriate response depends on the material, jurisdiction, parties, value, and intended use, so buyers, exporters, miners, refiners, investors, manufacturers, and public officers should confirm transaction-specific requirements before acting.
Official and primary sources