Alex Stewart international Rwanda’s laboratory has a unique competence: a trustworthy and recognized network that employs qualified and experienced chemists using state-of-the-art analytical equipment to deliver the most precise and prompt results. Our laboratory is fully equipped with traditional and modern instrumentation to provide a fast, reliable and accurate results.

Alex Stewart international Rwanda’s laboratory provides ISO 17025 designation in analytical services for 3Ts (Tin, Tantalum, Tungsten), Manganese, Iron, lithium and beryllium. Additional testing includes base and minor metals, ores and concentrates. We also offer a range of geological services to the mining and mineral exploration sector.

Alex Stewart International Rwanda’s laboratory tailors their services to deliver cost effective and fast turnaround analytical services without compromising quality and result accuracy. Overall, our laboratory is able to perform analysis for several elements of the periodic table.

Analytical Instruments include:

  • WDXRF Zetium and PW 1480: Determine principal and trace elements
  • ICP-OES Spectrometers: analysis of a wide range of elements at ppm for multi elemental accurate results
  • Atomic Absorption Spectroscopy: measure low levels of elements in all metallurgical materials
  • High Precision Titrators: fast and accurate determination of elements including Tin, Copper, Lead, Manganese, Iron and Chromium
  • UV/Visible spectrometer
  • Conductivity meter
  • Fluorimeter
  • PH-meter
  • Electro-gravimetric set

Services include:

  • Confirm the date sample(s) were received
  • Advise the date you expect your final results and certificates
  • Deliver fast turnaround and accurate results
  • Give a status report and provisional result updates
  • Release e-certificates and hard copy reports
  • Arrange additional tests as and when required
  • Offer technical advice and result interpretation
  • Provide professional and friendly customer service
  • Carry out all clients ‘work in complete confidentiality

Inspection and Analytical services

Inspections: Our strategically located inspection operations cover all of the Africa’s major load port for 3TS (Tin, Tantalum, Tungsten), base and minor metals, ores and concentrates.

Service include:

  • Full inspection
  • Supervision of loading operations
  • Weight determination by surveillance of shore scale
  • Weight determination by draft survey
  • Representative sampling
  • Moisture determination
  • Quality Sample preparation

Analytical services: Alex Stewart international Rwanda provides the complete service of accurate independent analysis for 3TS (Tin, Tantalum, Tungsten), base and minor metals, ores and concentrates. Analysis is performed by classical wet chemistry techniques, combined with state –of-the-art high-tech instrumentation including atomic absorption spectrometer, UV/VIS spectrometer, ICP emission spectrometer, and X-Ray fluorescence.

Analysis can be provided as a standalone service or combined with our representative sampling and inspection services, which are carried out through Alex Stewart International Rwanda ‘s office.

Inspection and analytical services are available for all base and minor metals, ores and concentrates including:

  • Tin concentrate
  • Tantalum concentrate
  • Tungsten concentrate
  • Copper
  • Zinc
  • Bauxite and alumina
  • Iron ore
  • Antimony
  • Bismuth
  • Chromium
  • Cadmium
  • Cobalt
  • Magnesium
  • Manganese
  • Molybdenum
  • Titanium
  • Silicon
  • Beryllium
  • Lithium

Mining Service and Geochemical analysis:

Comprehensive Geochemical services

Alex Stewart International Rwanda provides mining, geochemical and analytical services to the mining and mineral exploration industry in Africa.

Analytical Services

  • Preparation
  • Dissolution
  • Fusion
  • Trace level analysis
  • Calcinations

Instruments and Methods

  • WDXRF and EDXRF Spectrometer
  • Atomic Absorption Spectrometer –AAS
  • Multi element emission spectrometer by argon plasma –ICP-OES
  • Gravimetric determination
  • UV/VIS spectrometer


Laboratory are designated to ISO /IEC 17025 standard and participate to interlaboratory tests and international round robins.