Technical data for De Lank granite
De Lank is a fine to medium grained biotite granite from a single geological body, the Bodmin Moor granite. The figures below are from independent testing of the stone. Product-specific test reports and Declarations of Performance are supplied on request.
Download this data as a one-page A4 PDF →Strength
- Compressive strength (dry)
- 219 MPa
- Flexural strength
- 24.1 MPa
- Modulus of rupture
- 17.64 MPa
- Young's modulus
- 32.3 GPa
Physical
- Density
- 2644 kg/m³
- Water absorption
- 0.20%
- Open porosity
- 0.60%
- Abrasion resistance
- 17.9
- Salt crystallisation
- 0.69% weight loss
- Linear thermal expansion coefficient
- 7.243 x 10^-6
- Polished stone value (PSV)
- 53
Durability
- Frost resistance
- Not affected. Freeze-thaw result: 0.08% weight loss.
- Expected life
- Virtually indestructible. Expected lifespan equal to that of the building.
Slip resistance (USRV, wet)
- Dolly pointed (fine picked)
- 77
- Fine axed
- 75
- Flame textured
- 69
- Sawn
- 51
- Honed
- 45
- Polished
- 20
Mineral composition
- Quartz
- 43%
- Alkali feldspar
- 26%
- Plagioclase feldspar
- 21%
- Biotite mica
- 4%
- Muscovite mica
- 5%
- Tourmaline
- 1%
Proven in service, not only in the laboratory
The 1882 Eddystone Lighthouse has stood in the open Atlantic on De Lank granite for more than 140 years. The Thames Embankment walls have held a tidal river since 1870. Trafalgar Square has taken two decades of constant footfall on De Lank paving. For a specifier, that record answers the questions a test certificate cannot.
Need something beyond the standard range?
The Stone Range is our in-stock selection. De Lank also produces bespoke architectural stone to any specification — cladding panels, carved masonry, large-format paving and structural elements — for architects, developers and civil engineers.