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SSQ Group own and operate the San Luis quarry in La Repressa, deep in central Argentina, between the sprawling Pampas and the majestic Andes. Quarried for centuries, our prized reserves date back 560 million years to the pre-Cambrian era.
Every Riverstone slate comes from the same high quality seam of rock, so you can be sure that you’ll get consistent quality, effectiveness and extraordinary beauty with every single slate.


Slate is formed when mudrock is buried deep beneath the earth’s surface and exposed to great pressure and temperatures that would make the mercury in your thermometer boil instantly. When you leave slate ‘in the oven’ for a little longer, it becomes phyllite.



Hand split, just like slate, Riverstone natural phyllite has a slightly coarser grain and a unique satin-like luster, making it the choice of the most discriminating architects across the world.
Just as this satin ‘phyllitic sheen’ helps to distinguish phyllite from slate in the field, it will set your roof apart from all the rest.
There are only a handful of phyllite sources known worldwide, and even fewer that are able to split the stone at the thickness required to be suitable for use as a roof covering material.


Rivertstone undergoes 3 or 4 phases at the processing plant depending on the final product, prior to being packaged:
– Sawing: The large blocks of rock extracted from the quarry are sawn into different sizes in accordance with the size of the stone to be produced.

- Splitting: The slate is then hand split at desired thickness. The water ensures the blocks do not dry, facilitating exfoliation and reducing loss.

- Calibrating: The riven slates are then calibrated to exact thickness required.

– Shaping:Then, workers cut each piece into desired dimention, treating each item with meticulous care, all of which is done by hand.



After classification the slates are counted and packaged on wooden pallets for storage and subsequent delivery.
A label is placed on each pallet with a description of the slate (quarry and plant of origin, format, thickness, etc.); in addition to the name of the person in charge of selection.

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