Brazilian Black Honed Slate Hearth Slab | 1200×900×20mm

Direct-from-quarry Brazilian Black Honed Slate (1200 x 900 x 20 mm). Engineered with a calibrated 20mm thickness, a super-flat, smooth surface, and fully chamfered, honed edges. Part of our full Honed Slate Hearths range and our Slate Hearths range.

Highlights

• Calibrated 20mm Thickness: Ensures a flat, consistent bed height for quick, seamless installation.
• Ultra-Smooth Surface (Zero-Riven Finish): Machine-honed to a silky, mirror-flat sheen. Features subtle, cloud-like tonal movement produced naturally as the diamond honing process exposes the internal grain of the stone.
• Factory-Chamfered Edges: All four sides are precision-honed with micro-chamfered edges, eliminating harsh saw lines for an architectural finish right out of the crate.
• 14-Day Crack Guarantee: If your slab cracks within 14 days of delivery (provided it is installed within that same 14-day window), we'll replace it completely free.
• Free Photo Service: Free dispatch photo of your exact slab before delivery — always included on Premium grade, and on Standard grade when a cutting or finishing service is added.
• Order a sample: Choose up to 2 free samples for a flat £5 delivery fee. See the texture and quality in person before committing to a full slab. Order your sample

Engineered with a calibrated 20mm thickness, an ultra-smooth honed surface, and factory-chamfered edges. Exhibiting a sophisticated graphite-black tone with elegant, cloudy grain movement in its raw state, this high-density slate darkens into a deep, velvety charcoal when sealed. Ideal for luxury fireplace hearths where you want to make a statement. Available nationwide as single slabs, cut-to-size or full wholesale crates for trade buyers.

Technical Specifications

• Dimensions: 1200 x 900 x 20 mm (+/- 1mm)
• Thickness: 20 mm calibrated
• Weight: 62 kg per slab
• Surface Finish: Super-flat, satin-honed (zero-riven) with cloud-like grain movement
• Edge Finish: 4-side honed with factory-applied micro-chamfer
• Colour Profile: Raw state Graphite grey/black with soft cloudy grain; deep charcoal to rich black after sealing
• Slip Resistance: PTV 54 (Dry) / PTV 38 (Wet) – Low Slip Risk
• Flexural Strength: 19.6 MPa (48 Freeze-Thaw Cycles)
• Water Absorption: Less than 0.50% (High Frost Resistance)

Crack Guarantee

If your slab cracks within 14 days of delivery (provided it is installed within that same 14-day window), we'll replace it completely free.

Free Pre-Dispatch Photo Service

Every premium-grade order includes a free dispatch photo of your exact slab sent straight to you before delivery. Standard-grade slabs also include this service whenever a custom cutting or finishing service is added.

In-House Workshop Finishing & Fabrication Packages

Need custom cutouts, tailored edge profiles, or surface pre-treatments for visible hearth lips or steps? Select from our workshop options before dispatch:

Cutting Only

• Factory Straight Cut (C-01 / C-02): Laser-guided precision sawn (+/- 1.50mm) with re-honed edge matching.

Premium Signature Finish

• Bespoke Profile Match (S-01): Custom edge reprofiling (pencil round, full bullnose) matching the factory-honed sheen.

• Multi-Stage Face & Edge Honing (S-02): High-grit diamond pad refinement to restore mirror-smooth edges after custom workshop cuts.

• K30 Chemical Deep Clean (S-03): Extracts micro-slurry and fine hone dust trapped during polishing to ensure max sealer penetration.

• Stovax Dressing Oil / Satin Sealer Treatment (S-04): Professional-grade pre-sealing that locks in the rich, dark charcoal finish and provides instant oil and water stain protection.

See how our slate cutting, finishing, and sealing services work, from laser-guided cuts to bespoke edge profiles.

Ordering, Wholesale Crates & Nationwide Delivery

• Flexible Quantities: Buy individual slabs for precise cut-to-size hearth work, or full crates for trade project savings.

• Nationwide Logistics: Direct-to-site delivery via 3rd-party nationwide pallet networks. Offloaded by tail lift and delivered kerbside.

• Customer Quotes: Call 01908 46 46 56 or email drawings to sales@blueskystone.com.