The special appearance of Belgian bluestone

The special appearance of Belgian bluestone

Belgian bluestone is a natural and very compact limestone. Characteristic are the beautiful gray-blue hues and the many fragmentary fossil remains in the surface. The shimmering fracture surface of the stone is reminiscent of granite, explaining the alternative name “petit granit.

That special look of Belgian bluestone, how did it actually come about?
Belgian bluestone is a sedimentary rock, meaning it is formed from layers of accumulated sediment or organic material. It was formed from layers of calcareous material remains of underwater fauna and flora. And just what are those distinctive white flecks or “crinoids” in the hardstone quarried in Belgian Hainaut? In fact, the rock contains a high proportion of fossilized fauna. These residues are sometimes visible on the surface, and they usually increase the value of the material by their appearance. This bluestone was formed as much as 345 million years ago. Then, of course, there was a very different climate here. The Ardennes were part of a tropical sea full of corals. In the Late Devonian and Early Carboniferous, those corals formed thick layers of limestone at the bottom of the sea, which are now thus the bluestone.

So the white flecks in Belgian hardstone are the fossils of crinoids, also called sea lilies. Contrary to what the name suggests, they are not actually flowers, but a species related to starfish and sea urchins. In our area, these creatures were extremely common at the time, so blue stone now forms a beautiful whole full of white specks, the fossils of crinoids and other marine life. By the way, did you know that sea lilies are still found in the sea? Biologists consider them a “living fossil” because they have been present on Earth for so long, almost unchanged.

Most people love the special appearance of Belgian bluestone. Because they give your interior, facade or terrace a unique and authentic look. Sawn, Belgian bluestone shows all its natural variations of blue-gray colors. Further processing, such as sweetening or flaming, can accentuate or highlight the color nuances originally present. Each specific stone is unique.

You can also see white flecks in Asian blue stone. Yet these are not crinoids. They are oolites that oxidize over time and can even produce rust stains.

Click here to proceed to the article on the Aries Natural Stone website

View the projects of Ariës Natuursteen here

Back to blog