ISO 3262-13:2023

Overview

ISO 3262-13:2023 - "Extenders - Specifications and methods of test - Part 13: Natural quartz (ground)" specifies requirements and test methods for ground natural quartz used as an extender (filler). The second edition updates test references (for example ISO 8130-13 for particle size analysis) and replaces the 1997 edition. The standard covers composition limits, physical parameters, sampling, a gravimetric determination of silica content and the minimum information required in a test report.

Keywords: ISO 3262-13:2023, natural quartz, ground quartz, extenders, specifications and methods of test, silica content, particle size distribution, quality control.

Key topics and technical requirements

• Grades and composition
  • Two grades (A and B) with minimum quartz and SiO2 content: Grade A 97% and Grade B 80% (by mass) verified by X‑ray diffraction or X‑ray fluorescence/gravimetric methods.
• Physical limits (essential)
  • Residue on sieve (63 µm and 45 µm) - limits to be agreed between parties; 63 µm example max 0.1% shown.
  • Matter volatile at 105 °C: max 0.3% (ISO 787-2)
  • Loss on ignition: max 0.5% (ISO 3262-1)
  • Matter soluble in water (hot extraction): max 0.2% (ISO 787-3)
  • pH (aqueous suspension): 5.5 to 9 (ISO 787-9)
• Conditional requirements
  • Particle size distribution (instrumental) - ISO 8130-13 (laser diffraction)
  • Oil absorption (ISO 787-5), colour, lightness, resistivity of aqueous extract (ISO 787-14)
• Sampling and test reporting
  • Sampling according to ISO 15528.
  • Test reports must identify the product, reference ISO 3262-13:2023, present results and methods, note deviations or anomalies, and give test dates.

Silica determination (brief)

The standard specifies a gravimetric procedure for silica content involving ignition, treatment with sulfuric and hydrofluoric acids, repeat ignition and weighing to calculate SiO2 mass fraction. (Refer to Clause 6 of ISO 3262-13:2023 for the detailed test method and safety considerations.)

Applications and users

• Manufacturers and suppliers of extenders and mineral fillers
• Paints, coatings and plastics manufacturers specifying fillers for formulations
• Quality control and analytical laboratories performing compliance testing
• Procurement/specification engineers and regulatory bodies assessing material conformity

Practical uses include incoming material inspection, supplier qualification, product specifications for coatings/resins, and R&D when selecting or comparing ground quartz extenders.

Related standards

• ISO 3262-1 (general test methods)
• ISO 8130-13 (particle size by laser diffraction)
• ISO 787 series (general methods for pigments and extenders)
• ISO 15528 (sampling)
• ISO 18451-1 (terminology)
• ISO 3696 (water for analytical use)

For full test procedures, limits and safety details consult ISO 3262-13:2023.