Black Mist Granite Processing Techniques 

The Black Mist Granite is a fine- to medium-grained gabbro, by heart uniform black heart and subtle light gray clouds/veinswhich lend a soft movement to the dark background. It is considered one of the most commercial black granites in the American market, often used as an alternative to Black São Gabriel and Via Láctea..

Average Mineralogical Composition

• Plagioclásio (labradorita): 45–55%
• Pyroxene (augite) and mafic minerals: 30–40%
• Biotite and iron oxides: 5–10%
• Quartzo: traços (<3%)

Properties

• Hardness: 6–7 Mohs → high scratch resistance.
• Water absorption: 0.2%–0.3% (low).
• Compressive strength: >200 MPa.
• Durability: excellent for indoor and outdoor environments.

It is a very stable stone, but some batches may present microcracks or lighter areas susceptible to oxidation, which requires the marble worker's attention.

 INFORMATION TO THE MANUFACTURER (Marbler)

Recommended finishes

• Polish: most popular finish, enhancing the black background with gray clouds.
• Brushed (Leather): current trend for kitchens and gourmet countertops.
• Levigated: elegant matte finish, excellent for indoor floors.
• Flamed + Brushed: ideal for outdoor and non-slip areas.

Processing and Cutting

• This material has good workability, allowing for straight cuts and rounded moldings.
• Use high-performance diamond blades for granite (e.g., 350 mm OS-31SS or Diapar DP-1015).
• Be careful when cutting blocks with microcracks: reinforce with epoxy resin before polishing.

Waterproofing

Despite its low absorption, it is recommended to waterproof countertops and floors to prevent grease stains and signs of wear.

Recommended products:

• Brazil: Rock Protect – Chemistone / Nano Effect – AKEMI / Idea Gold – Bellinzoni
• Abroad: Proseal – Tenax / Stain Proof – Dry Treat / Idea Gold – Bellinzoni

Procedure:

• Apply to a clean, dry surface with a brush or roller.
• On floors and facades, also protect the sides before installing.
• Reapply every 2–3 years in high-use areas.

Gluing the Parts

• Use epoxy or polyester adhesives specifically for granite (Tenax Fix Top, Bellinzoni Blitz Mastique, Argacon Marmofix).
• Pigment the adhesive black or gray to even out the joints.

Settlement

• Benches: Support every 60 cm on metal corners, bonded with white/black PU40. Avoid industrial silicones (they can stain).
• Indoor/outdoor floors: Lay with white/gray ACIII mortar. Flexible grout. Apply a water repellent after the mortar has cured.