ISO 7404-2:2009 PDF

Overview

ISO 7404-2:2009 - Methods for the petrographic analysis of coals - Part 2: Methods of preparing coal samples defines standardized procedures for preparing polished particulate blocks (and embedded lumps) from crushed coal for analysis by reflectance microscopy. The standard describes sampling preparation, required apparatus and materials, binder selection, moulding and curing considerations, and grinding/polishing and cleaning regimes to produce a relief‑free, scratch‑free surface suitable for petrographic study.

Key topics and technical requirements

• Scope and principle: Produce a representative, polished surface exposing at least 50% coal for microscopy and reflectance measurements.
• Sample preparation: Air‑drying per ISO 18283, size reduction to pass a 1.00 mm sieve, and laboratory sample division (50–100 g) to ensure representativity.
• Binders and mounting: Properties required include chemical inertness, compatibility with immersion oil, suitable curing temperatures (preferably