Black Knight
December 17, 2019
Why do we love this stone?
The colour grey is often associated with terms dull, dirty, and dingy. However this Alpine Grey is anything but. It is formal and sophisticated while offering a conservative elegance. This is a timeless stone that you will never need to change.
The technical stuff
It’s cool, we get it, you want to know absolutely everything about this stone. Well here you go, go nuts.
| Specification |
Typical |
| Slab size nominal |
3200 x 1600 x 6.5mm |
| Slab thickness tolerance |
+/- 0.70mm |
| Slab flatness |
+/- 1mm width | +/- 2mm length |
| Gloss |
56 |
| Slab weight |
58kg |
| Property |
Test Method |
Typical Value |
| Specific Gravity |
ASTM D792 |
2.40 |
| Hardness |
MOHS |
7.6 |
| Water Absorption |
AS 1756-1989 (AS-3558.1) |
0.03% |
| Colour Fastness |
AS 1756-1989 (AS-3558.3) |
No Change |
| Impact Resistance |
AS 1756-1989 (AS-3558.15) |
No Cracks or Grazing |
| Impact Resistance |
EAN1467.9 |
3.30j Unsupported 6.1j Supported |
| Izod Impact Resistance |
ASTM D256 |
2.23ft.lbf |
| Flexural Strength |
ASTM D790 |
47Mpa |
| Resistance to Surface Scratching |
AS 1756-1989 (AS-3558.4) |
Unaffected |
| Resistance to Surface Scratching |
AS/NZS 2924.2.14 |
6.5N |
| Wear Index |
ASTM D4060 |
0.58mg/cycle |
| Heat Resistance |
NEMA D2863 |
No Change |
| Steam Resistance |
AS/NZS 2924.2.23 |
No Change |
| Boiling Water Surface |
NEMA LD-3 |
No Change |
| Stain Resistance |
AS 1756-1989 (AS-3558.42 |
Pass. Any superficial stains were removed by water, undiluted bleach or Jiff. |
| Slip Resistance |
AS/NZS 4586 Dry |
Class F (Medium) |
| Slip Resistance |
AS/NZS 4586 Wet |
21 |
| Thermal Shock |
ASTM C484 |
No cracks or crazing |
| Heat Release |
AS/NZS 3837 |
Total Heat Released 50.1 MJ/kg |
| Average Specific Extinction Area |
AS/NZS 3837 |
153.1 m2/kg |
| Critical Heat Flux |
ASISO 9239.1 |
4 |
| Early Fire Hazard Ignitability Index |
AS1530.3 0-20 |
4 |
| Early Fire Hazard Spread of Flame Index |
AS1530.3 0-10 |
0 |
| Early Fire Hazard Heat Evolved Index |
AS1530.3 0-10 |
2 |
| Early Fire Hazard Smoke Developed Index |
AS1530.3 0-10 |
2 |
