--- title: "Properties of marble, slate, granite" subject: "Engineering Geology I" chapter: 4 key: "semester_3/engineering_geology_i:properties-of-marble-slate-granite" source: https://www.bctengineer.com/q/semester_3/engineering_geology_i/properties-of-marble-slate-granite site: BCT Engineering --- # Properties of marble, slate, granite Engineering Geology I · Chapter 4: Petrology - Asked in: 2078 Kartik, 3+4 marks - Video: [Every Type of Natural Stone Explained in 8 Minutes](https://www.youtube.com/watch?v=qs_ClLCyNpg) — OwlExplained - Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14 - Page: https://www.bctengineer.com/q/semester_3/engineering_geology_i/properties-of-marble-slate-granite - Whole chapter: https://www.bctengineer.com/md/semester_3/engineering_geology_i/chapter-4 ## Question Write down the physical and engineering properties of marble, slate and granite. ## Short answer Marble (metamorphic, calcite) has hardness 3-4, strength 70-140 MPa, is acid-soluble, and is used for decoration. Slate (metamorphic, mica) shows slaty cleavage, strength 70-200 MPa, low absorption, and serves for roofing. Granite (igneous, quartz-feldspar) has hardness 6-7, strength 100-250 MPa, very low porosity, excellent durability, and is used for foundations and aggregate. ## Answer Marble (metamorphic, from limestone), slate (metamorphic, from shale) and granite (igneous, plutonic) are common building stones. The values below are typical textbook ranges. #### Physical properties | Property | Marble | Slate | Granite | |---|---|---|---| | Origin | Metamorphism of limestone/dolomite | Low-grade metamorphism of shale | Slow cooling of acidic magma at depth | | Colour | White, pink, green, black (veined) | Grey, black, green, purple | Pink, grey, white with dark specks | | Texture | Granoblastic, crystalline, granular | Very fine grained, dense | Holocrystalline, medium to coarse, granular | | Structure | Massive, non-foliated | Slaty cleavage (splits into thin sheets) | Massive, uniform | | Main minerals | Calcite (dolomite) | Mica (sericite), chlorite, quartz | Quartz, orthoclase feldspar, mica/hornblende | | Specific gravity | 2.6 - 2.8 | 2.7 - 2.8 | 2.6 - 2.8 | | Hardness (Mohs) | 3 - 4 | 3 - 4 | 6 - 7 | | Lustre | Vitreous to sugary, takes high polish | Dull to silky | Vitreous, takes polish | #### Engineering properties | Property | Marble | Slate | Granite | |---|---|---|---| | Compressive strength | 70 - 140 MPa | 70 - 200 MPa (higher perpendicular to cleavage) | 100 - 250 MPa | | Water absorption | Very low (<1 %) | Very low (<1 %) | Very low (<0.5 %) | | Porosity | Low | Low | Very low | | Weathering resistance | Poor in acidic/polluted air (calcite dissolves) | Good | Excellent | | Workability | Easy to cut, carve and polish | Easy to split into thin slabs | Hard to dress; takes a good polish | - Marble: flooring, facing, steps, monuments; unsuitable for exposed outdoor use where there is acid rain. - Slate: roofing sheets, flooring, damp-proof courses, paving; weak along cleavage. - Granite: heavy foundations, bridge piers, retaining walls, dam facing, road aggregate, ballast and kerb stones; durable, and fire resistant up to about 600 °C. ## Check yourself The answer's key points as multiple-choice questions, with the correct option and why. 1. Which has hardness 6-7? A. Marble B. Slate C. Granite D. Both marble and slate Answer: C. Marble and slate are 3-4. (Key point: Hardness) 2. Which weathers poorly in acid rain? A. Granite B. Slate C. Quartz D. Marble Answer: D. Calcite dissolves. (Key point: Weathering) 3. Slate A. splits into thin sheets B. is massive C. is coarse D. has no cleavage Answer: A. It has slaty cleavage. (Key point: Slate) 4. Granite is used for A. roofing sheets B. heavy foundations, bridge piers, aggregate, ballast C. statues only D. lime Answer: B. Fire resistant to about 600 C. (Key point: Granite uses) ## Close variants set in other exams - [Properties of marble, slate, amphibolite](https://www.bctengineer.com/question.md?key=semester_3%2Fengineering_geology_i%3Aproperties-of-marble-slate-amphibolite) — Engineering Geology I, chapter 4, asked 2× ## Related in Engineering Geology I - [Properties of granite, limestone, shale, marble](https://www.bctengineer.com/question.md?key=semester_3%2Fengineering_geology_i%3Aproperties-of-granite-limestone-shale) — Engineering Geology I, chapter 4 - [Engineering significance of marble, granite, sandstone](https://www.bctengineer.com/question.md?key=semester_3%2Fengineering_geology_i%3Aengineering-significance-of-marble-granite) — Engineering Geology I, chapter 4 - [Engineering uses of granite and marble](https://www.bctengineer.com/question.md?key=semester_3%2Fengineering_geology_i%3Aengineering-uses-of-granite-and) — Engineering Geology I, chapter 4 - [Properties and uses of granite, phyllite, limestone](https://www.bctengineer.com/question.md?key=semester_3%2Fengineering_geology_i%3Aproperties-and-uses-of-granite) — Engineering Geology I, chapter 4, asked 4× - [Identify metamorphic rock; properties of sandstone and granite](https://www.bctengineer.com/question.md?key=semester_3%2Fengineering_geology_i%3Aidentify-metamorphic-rock-properties-of) — Engineering Geology I, chapter 4 - [Texture and properties of quartzite, limestone, granite](https://www.bctengineer.com/question.md?key=semester_3%2Fengineering_geology_i%3Atexture-and-properties-of-quartzite) — Engineering Geology I, chapter 4, asked 2× ## Related in other subjects - [Physical and mechanical properties of wood](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Aphysical-mechanical-properties-wood) — Civil Engineering Materials, chapter 7 - [Physical properties of OPC and concrete behaviour](https://www.bctengineer.com/question.md?key=semester_5%2Fconcrete_technology_and_masonry_structure%3Acement-physical-properties) — Concrete Technology and Masonry Structure, chapter 1 - [Important properties of civil engineering materials](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Aimportant-properties-civil-materials) — Civil Engineering Materials, chapter 1, asked 8×