What does F1 of WJEC A-Level Geology cover?

F1, Elements, Minerals and Rocks, is the first of the Fundamentals of Geology units. It covers the most abundant elements in the crust, the silicon-oxygen tetrahedron and how silicate structures (isolated, chain, sheet and framework) control mineral properties, the diagnostic physical properties used to identify minerals in hand specimen, the three classes of rock and how to recognise them, and the rock cycle that links the classes.

How is mineral and rock identification tested in WJEC A-Level Geology?

Identification is a Component 1 practical skill. You are given hand specimens and photographs of minerals, rocks and fossils to identify and describe, so you must know the physical properties (hardness, cleavage, fracture, lustre, colour, streak, density, habit), the silicate families, and the textures that define igneous, sedimentary and metamorphic rocks. The acid test, a hand lens and a streak plate are standard tools.

What is the silicon-oxygen tetrahedron and why does it matter?

The silicon-oxygen tetrahedron is one silicon ion surrounded by four oxygen ions and is the building block of all silicate minerals. How many corner oxygen atoms each tetrahedron shares with neighbours defines the structural family, from isolated olivine through chain and sheet silicates to framework quartz and feldspar, and this controls cleavage, hardness, density and the order of crystallisation.

How do I tell the three rock classes apart in hand specimen?

Use texture first. Igneous rocks have interlocking crystals with no cement, bedding or fossils, and crystal size records cooling rate. Clastic sedimentary rocks have separate grains held by cement, with bedding, sorting and often fossils. Metamorphic rocks show foliation (aligned platy minerals from directed pressure) or a recrystallised non-foliated texture such as marble or quartzite.

What drives the rock cycle?

Two energy sources. Internal heat from radioactive decay and residual heat of formation drives mantle convection and plate tectonics, causing melting, metamorphism and uplift at depth. External solar energy drives the atmosphere and water cycle, powering weathering, erosion, transport and deposition at the surface, with gravity moving material downhill.

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WJEC A-Level Geology F1 Elements, Minerals and Rocks: a deep dive on crustal elements, silicate structures, mineral identification and the three rock classes

A deep-dive WJEC and Eduqas A-Level Geology guide to F1, Elements, Minerals and Rocks. Covers the abundant crustal elements, the silicon-oxygen tetrahedron and silicate structures, mineral identification by physical properties, the three rock classes and the rock cycle, with exam-style worked questions.

Generated by Claude Opus 4.816 min readWJECUpdated 2026-06-16

Reviewed by: AI editorial process; not yet individually human-reviewed

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What F1 actually demands
Elements and silicate structures
Identifying minerals
Rock classes and the rock cycle
Check your knowledge

What F1 actually demands

F1 builds the vocabulary and the practical eye of the whole course. Examiners want secure definitions, structural reasoning that links silicate bonding to physical properties, and fast, confident identification of minerals and rocks in hand specimen and photograph. Because the practical paper (Component 1) draws specimens straight from this unit, the properties and textures must be automatic, not looked up.

This guide ties the four topics of the unit together. Each has a matching dot-point page with practice questions; this overview connects them.

Elements and silicate structures

Eight elements make up almost all of the crust, with oxygen and silicon dominant, which is why silicate minerals are so common. The silicon-oxygen tetrahedron is the building block, and the degree to which tetrahedra share oxygen atoms (isolated, single-chain, double-chain, sheet, framework) sets the silica content, the density, the crystallisation temperature and the cleavage. Olivine (isolated) is dense with poor cleavage; mica (sheet) splits into flakes along weak interlayer planes; quartz (framework) has no cleavage and high hardness.

Identifying minerals

Mineral identification uses a small toolkit of diagnostic properties: hardness on the Mohs scale (with nail, coin and blade as references), cleavage (directions and angles), fracture, lustre, colour, streak (the powder colour, more reliable than colour), density and crystal habit. Hardness, cleavage and the acid test together separate the common minerals quartz, feldspar, mica and calcite.

Rock classes and the rock cycle

Rocks are classed by process: igneous (from melt), sedimentary (deposited and cemented) and metamorphic (altered in the solid state). Texture is the key to recognition. The rock cycle connects the classes through weathering, erosion, transport, deposition, lithification, metamorphism, melting and crystallisation, driven by internal heat and solar energy with gravity.

Check your knowledge

Attempt these under timed conditions, then check against the solutions.

Define a mineral and a rock. (2 marks)
Name the silicate structural family of mica and explain its perfect cleavage. (3 marks)
State two properties that distinguish quartz from calcite. (2 marks)
Describe the texture that identifies a rock as igneous. (2 marks)
Place weathering, lithification, deposition, transport and erosion in the order they act on rock at the surface. (2 marks)
State the two energy sources that drive the rock cycle. (2 marks)

Sources & how we know this

WJEC Eduqas A-level Geology specification — WJEC Eduqas (2017)