PORTORO — black and gold marble from Portovenere, slabs and blocks

The gold that nature sealed inside the stone. The rarest black marble in the world, selected block by block for three generations.

Discover the collection Imagine it in your home

Portoro

It is born in a single place on earth, the cliffs of Portovenere. Nature took two hundred million years to draw its golden veins. We choose only the blocks where the gold is perfect.

A single ray of light reveals new golden veins: Portoro never looks the same twice.

Book-matched

Two slabs,
one single design

Cut one after the other from the same block and opened like the pages of a book. The veins mirror each other and the wall becomes a one-of-a-kind work.

In your home

Imagine coming home

A wall that glows with warm light in the evening. An island that seems carved from a single block. Choose a room and move the cursor to look around.

Bathroom. A book-matched wall from floor to ceiling, a floating basin cut from a single block, a mirror with golden light.

Three grades, one stone

Every block is graded at the quarry by the depth of its black and the continuity of its gold. Move closer to the slab to see the veins.

Premium

First grade

A deep, even sepia-black ground with continuous golden veins. For walls and floors where every slab takes centre stage.

Extra

Bold pattern

Denser, more pronounced gold with strong character. Designed for countertops, basins and surfaces seen up close.

First choice

Large surfaces

The same Portovenere stone with freer veining. The choice for cladding large spaces consistently.

Hover over the slab to zoom in

See the slabs available in the online showroom

Company

One family,
one marble

Since 1922 the Santella family has quarried and traded Portoro. The grandfather owned a quarry on Mount Castellana, in the Gulf of La Spezia, and shipped his blocks around the world.

Today GS Marmi follows every step from quarry to installation: block inspection, selection, slab cutting, all the way to the most exclusive projects.

1922Founded

52+Luxury projects

1Deposit in the world

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