This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
CaOHSEM. en Scanning electron microscopy image of fracture surfaces of hardened cement paste showing plates of calcium hydroxide and needles of ettringite micron scale fhwa dot gov cfm US Department of Transportation PDUSGov Calcium compounds
Page 2023 Free-images.com. All images are Public Domain