METALS & MINERALS

Alex Stewart International provides assaying and analytical services for base, minor and precious metals including jewellery, ores and concentrates, ferro alloys, recycled scrap metal, metallurgically complex materials and plastics.

Through Alex Stewarts International's operations network, we can also provide you with weighing, sampling and inspection services. Our professional and technically knowledgeable team provide a dedicated, high quality service to meet the specific requirements of the metal industry, mining companies, traders, metal producers and refiners, governments, banks and financial institutions and the general public.

Base Metals – Ferrous Ores and Concentrates

Alex Stewart International provides a complete service of independent accurate analysis for base metals, ores and concentrates. Analysis is performed by classical wet chemistry techniques, combined with state-of-the-art high-tech instrumentation including Atomic Absorption, ICP, Carbon Sulphur and XRF.

Complete sampling and analysis is available for:

Our strategically located inspection operations (please refer to interactive map) cover all major load and discharge ports and refineries for base and non-ferrous metals, including all leading South American, Asia Pacific and European ports, refineries and warehouses. Services include full inspection, draft survey, transportable moisture limits, shore scale or belt weighing surveillance, stockpile control and sampling.

Ferro Alloys & Minor Metals

Sampling and analysis for Minor Metals and Ferro alloys includes:-

Mining Services and Geochemical Analysis

Alex Stewart International provides mining, geochemical, environmental, metallurgical and analytical services to the mining and mineral exploration industry in Africa, Europe, South America and Asia.

Alex Stewart International is able to design, install and staff laboratories at for major exploration projects at mining sites almost anywhere in the world.

Laboratories are accredited to ISO 9001, 14001 and 17025 standards and participate in inter-laboratory tests and international round robins

Analytical Services 

Instruments and Methods

Jewellery and Gold Testing

We will weigh, test and analyse any gold or precious metal containing jewellery including earrings, bracelets, necklaces, rings, filings, chains, watches, pendants, coins, sovereigns and krugerands. Tests are determined by rapid XRF which is able to provide detailed analysis by measuring the intensity of the generated gold X-rays by wavelength dispersion analysis. This technique is essentially non-destructive and minimal sample preparation permits very fast turnaround times.

When testing is complete, a full report indicates the percentages of gold content as well as other alloying metals such as copper, silver, zinc, etc. This method is remarkably accurate. Having tested for gold, we will then send you an official certificate of its content and approximate value at current market prices.

Precious Metals

Alex Stewart International provides analytical, sampling and inspection services at major precious metal refineries in conjunction with Alex Stewart International's network of offices in Africa , Americas , Asia , Australia and Europe.

Inspection services include weighing, representative sampling and supervision of melting at refinery or bonded warehouse.

Analytical Services for precious metals are by classical chemistry methodology, gravimetric titration, fire assay, Atomic Absorption, ICP and XRF and materials include:-

Scrap & Recycled Metals

Alex Stewart International can provide quantity and quality certification for ferrous, non-ferrous, electronic or plastic scrap material conforms to all contractual terms, conditions and also including all international regulations such as ISRI and GOST.

Digital photographic evidence will be provided for all Pre-shipment Inspection and Proof on Arrival for scrap metal inspections, inspection during loading and sealing of containers. Radioactivity testing and checking for the presence of hazardous or dangerous materials will also be rigorous to protect you from any unnecessary financial or environmental claims. Materials inspected include:-

RoHS and WEEE Screening Tests

Rapid XRF screen testing of electronic components and PCB's is performed in accordance to the Restriction of Hazardous Substances (RoHS) and Waste Electrical and Electronic Equipment (WEEE) Directives. This means that to comply with RoHS and WEEE you must be sure that your products are checked. Our screening tests will verify the percentage of harmful elements in line with the RoHS directive.

Whether your organization is the manufacturer of products, a supplier to the end manufacturer or recycles electronic scrap by testing electronic components, household appliances, telecommunications equipment, toys and other consumer goods you will receive our certificate which confirms whether or not your product contains lead, mercury, cadmium, hexavalent chromium, polybrominated biphenyls. If evidence is found then further in depth analyses can be applied. We are available to discuss and help you comply with RoHS and WEEE Directives.

XRF Detection Limits

• Cadmium 100ppm
• Chromium, Lead, Mercury, Bromine 1000ppm

All analysis can be combined with representative sampling and inspection services carried out by Alex Stewart International's network of offices in Africa, Americas, Asia, Australia and Europe. Please refer to our Global Operations Map for further details or for further information, please email: analysis@alexstewartinternational.com or call +44 151 525 1488.