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The stone that removes CO₂

The unique attribute of greenSand is that it permanently removes CO₂ from the air, in a way that nature has been doing it for billions of years: with the mineral Olivine. But what is so special about this rock? Olivine is a volcanic rock that makes up more than 50% of the Earth’s upper mantle, meaning that it is one of Earth’s most common and abundant minerals. Large Olivine deposits can be found all over the globe. The best and most important thing about it is that Olivine is a CO₂-absorbing mineral. CO₂ removal through rock weathering is an effective and natural approach to fight and reverse climate change.

Olivine mineralization

The carbon removal process starts when the CO₂ in the atmosphere reacts with rainwater, making the rainwater more acidic. This can be compared to sparkling water, in which the carbon dioxide adds sparkling bubbles to the water. Next, this acidic rainwater falls onto the greenSand Olivine rock, where a (natural!) chemical reaction is initiated between CO₂, water and the mineral Olivine. This process is called weathering. During the weathering process the CO₂ is being mineralized. In other words: CO₂ dissolves into different substances. The final result of the reaction is a solid end product made up of Magnesium, Bicarbonate and Silica, which are nourishing elements for the soil. Its chemical formula is:

greenSand + CO₂ + water => Magnesium + Bicarbonate + Silica
Mg₂SiO₄ + 4CO₂ + 4H₂O => 2Mg²⁺ +4HCO^3- + Si(OH)₄

Enhanced Weathering

This reaction occurs naturally and nature has been doing exactly this for millions of years. Weathering of Olivine rocks is nature's own mechanism to absorb carbon dioxide and keep CO₂ levels in balance. But there is a huge problem: human activities have caused CO₂ levels to increase drastically, which makes it impossible for nature to keep up, given the fact that the natural process of rock abrasion and weathering is very slow. Why not copy nature's mechanism and accelerate it? greenSand's mission is to do exactly that!

The weathering speed depends on the size of the Olivine rocks: the smaller the material, the faster it weathers and removes CO₂. Therefore, greenSand crushes and grinds Olivine to increase its surface area, which means that more CO₂ will be removed at a faster pace. In the Netherlands, we import a lot of sand and stone types. Many of these products can be replaced by greenSand products. Stones and sand are essential materials that are used in many different fields, and the same goes for greenSand products: they are used, among other things, for walking paths, cycle paths, parking lots, and in the form of soil for gardening. Join the movement and spread Olivine against CO₂! Let's help the Earth heal itself.