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Certified Quality

The leading international institutions have certified the quality of all our natural slates, ensuring ideal performance under any climate conditions.

pizarra natural tejado

NF Certification

The French NF mark ensures the quality, safety and performance of natural slate products.

CE Marking

Our natural slate exceeds the standards required by European Union regulations.

ATG Certificate

Voluntary technical approval of construction products conducted by the Belgian UBAtc institution.

UKCA Marking

The UKCA (UK Conformity Assessed) label is the new mandatory seal for products in the United Kingdom.

Laboratory Tests

All our natural slates are subject to laboratory tests to certify their excellent quality.

Water absorption

A1 (0,3%)

Thermal cycle


Exposure to SO2




Carbonate content, CaCO3

A1 (0,3%)

Non-carbonated carbon content



Flexural strength - Longitudinal

> 64 Mpa


Flexural strength - Transverse

> 55 Mpa

Downloading Certificates

You can download the official certificates for all our products simply and automatically from here.

Luz 25 Slate

Luz 30 Slate

Luz 40 Slate

Luz 55 Slate

Luz 115 Slate