Portuguese LSI Stone turns vice to virtue by artfully filling faults in limestone to create unique marketing material

LSI Stone’s limestone with Onyx was presented at Marmomac 2017. Photo: LSI Stone

The company’s headquarters are in close proximity to stalactite caverns, so once in a while small zones with Onyx marble can be found in its quarry

In the dubious interest of uniformity, today’s preferred implementation of natural stone, a great portion of material quarried is no sooner mined than turned to „waste“. But marble, granite and other natural stone inherently include irregularities such as breaches, making a block useless, or veins which might lend a unique touch.

One distinguishing factor of limestone was turned to a virtue by LSI Stone.

The company headquarters are right next to the Parque Natural das Serras de Aire e Candeeios where a limestone massif (Maciço Calcário Estremenho) artfully created some 1500 stalactite caverns. The Grutas de Mira de Aire are among them being one of the seven natural wonders of Portugal.

Mineral-rich water flowed though the limestone for millions of years – so, too, through the LSI Stone quarry where stalactites were formed.

In this particular case the stalactites are comprised of Onyx marble, a special type of onyx.

When raw blocks are sawed at the mill, the faults are revealed. LSI sorts out the slabs as every stone producer would.

But the faulted pieces are not discarded. Instead, they are stabilized by means of resin application and subsequently polished.

In cooperation with GPI a special back-mounted light source brings out the best in color and structure of the onyx. Thus, slabs of particular aesthetic value ensue.

Stone treated in this manner will be marketed as „Made by LSI“ Onyx. The brand is currently being registered.

Of course, onyx of this type can only be a niche product not suitable for mass production as available from Turkey or Iran.

But, according to LSI-CEO Regina Vittorio: „It is suited to prove once more that Portuguese natural stones’ diversity and the company’s craftsmanship are forces to be reckoned with.“

The value of this „waste product“ lies in its marketing potential.

LSI Stone

Grutas de Mira de Aire





(22.04.2018, 04.22.2018)