← The JournalSlab Arrival · March 2026
Antolini Kosmos Quartzite slab Super Cleft Texture finish on a crane in the Royal Stone yard, charcoal grey ground with silver mica, paler swirled veining and rust passages, 129 by 74 inches
Slab in daylight

Tap to toggle between daylight and the same slab backlit at the yard.

Kosmos is one of the dense, deep-grey quartzites in current Antolini production — a charcoal ground shot through with silver mica, ribboned with paler grey swirls and the occasional rust passage where iron oxidized through the bed. Polished, it reads close to a hard-rock granite. The story changes completely with Antolini's Super Cleft Texture finish.

Super Cleft is not a sandblast and not a leather. It is closer to a controlled fracture: the surface is split along the stone's natural cleavage planes and left there. No diamond pads, no resin fill. What you see in the close-up below — the rough, broken-open rock face, the mica catching light at every angle, the rust ghosting through the grey — is the raw quartzite as it leaves the block. The hand reads it as rock, not as countertop.

It is closer to a controlled fracture: the surface is split along the stone's natural cleavage planes and left there.
From the slab arrival, March 2026

This is the largest format Antolini produces this finish in: 129″ × 74″ jumbo, single slab. At that size the cleft texture starts behaving architecturally — the surface absorbs light the way a stacked-stone wall does, but with the visual continuity of a single piece. No grout joints, no veneer reads. One face, one stone, the full elevation.

The installed reference pictured below is from a Westside primary living room currently in finish — a freestanding double-sided fireplace mass clad floor-to-ceiling in Kosmos Super Cleft, sitting on a honed black soapstone hearth and base, with the firebox glazed full-height in clear glass on three sides. The two angles show the same mass: one looking at the front elevation through the firebox, the other reading the corner return and the side face. Note how the Super Cleft texture works across both planes — light catches the mica differently on the side that faces the windows than on the side that faces the room, and the wrapped corner reads as a single broken-rock monolith rather than two clad faces meeting.

On the floor at 2303 South Sepulveda. This is one of those slabs that has to be walked — photographs flatten the texture, and the difference between Super Cleft in yard daylight and Super Cleft on a finished fireplace mass is most of the specification decision. Designers and architects working in Los Angeles, Beverly Hills, Bel Air, Pacific Palisades, and Malibu — call and we'll pull it for you.

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AntoliniQuartziteKosmosSuper CleftJumbo SlabSlab Arrival

In place

The stone, installed.

Reference photography of this slab — or stone from the same selection — finished and at home in completed work.

  • Antolini Kosmos Quartzite Super Cleft Texture installed as a freestanding double-sided fireplace mass with a full-height glass firebox and a honed black soapstone hearth and base, in a Westside primary living room in finish stage
    Westside primary living room — front elevation, glass firebox on honed black soapstone hearth.
  • Side-angle view of the same Antolini Kosmos Quartzite Super Cleft Texture fireplace mass, showing the wrapped corner return reading as a single broken-rock monolith across two faces
    Same mass, corner return — the wrap reads as one broken-rock monolith.

Visit the Yard

See the stone
in natural light.

Royal Stone is a working slab yard. Designers and private clients are received by appointment Monday through Friday, 8:00 am to 4:30 pm.

2303 S Sepulveda Blvd

Los Angeles, CA 90064