Charcot–Leyden crystals - Wikipedia
Source: wikipedia.org
Why Roman Concrete Endured Thousands of Years of Seawater Pounding, While Ours Can't - ExtremeTech: Roman concrete's durability and strength blows our own out of the water (in this case, literally). And after years of research, we're getting better at understanding why. It seems that the sea water may...
Source: extremetech.com