Its tendency to split into thin plates has also made it a popular roofing material .
Slate is a popular choice of stone for memorials and inscriptions , as its fine grain and hardness means it leaves details very sharp .
Slate 's tendency to split into thin plates has also made it a popular roofing material .
Slate is a popular choice of stone for memorials and inscriptions , as its fine grain and hardness means it leaves details very sharp .