Yuav Ua Li Cas Xaiv Cov Khoom Siv Pob Zeb Zoo Lub Tsev
Aug 08, 2020
1.Appearanceandcolour: Stoneswithmuchironshouldbediscourageedastheformationofironoxidesdisfiguresthemandbringsaboutdisintegration.
2.Hardnessandtoughness: Agoodbuildingstonemustbehardandtough.Hardnessmaybetestedbyscratchingbypenknifeandtoughnessbysubjectingittohammeraction.
3.Strength: Buildingstonesshouldbestrongincompression.
4.Porosityandabsorption: Stoneswithmuchporesareunsuitablecauseofwaterseepingintoporeswithacidsandfumesdestroythestone.Watermayfreezeatcolderclimateandhencesplitthestone.
Finenessofgrains: Finegrainedaresuitableformouldingworks.
