abs , ▁v ases , ▁tomb st ones , ▁decor ative ▁architect ural ▁work , ▁em ery ▁whe els ▁and ▁gr ind st ones . ▁ ▁This ▁was ▁followed ▁by ▁Victoria ▁stone , ▁which ▁compr ises ▁three ▁parts ▁fin ely - cr ushed ▁Mount s or rel ▁( Le ic esters hire ) ▁gran ite ▁to ▁one ▁of ▁Port land ▁c ement , ▁mechan ically ▁mixed ▁and ▁cast ▁in ▁m ould s . ▁When ▁set ▁the ▁m ould s ▁are ▁lo os ened ▁and ▁the ▁blocks ▁placed ▁in ▁a ▁solution ▁of ▁sil icate ▁of ▁s oda ▁for ▁about ▁two ▁weeks ▁to ▁ind ur ate ▁and ▁hard en ▁them . ▁Many ▁manufact ur ers ▁turned ▁out ▁a ▁very ▁non - por ous ▁product ▁able ▁to ▁resist ▁cor ros ive ▁sea ▁air ▁and ▁industrial ▁and ▁resident ial ▁air ▁poll ution . ▁ ▁Most ▁later ▁types ▁of ▁artificial ▁stone ▁have ▁consisted ▁of ▁fine ▁c ement ▁concrete ▁placed ▁to ▁set ▁in ▁wooden ▁or ▁iron ▁m ould s . ▁It ▁could ▁be ▁made ▁more ▁cheap ly ▁and ▁more ▁uniform ▁than ▁natural ▁stone , ▁and ▁was ▁widely ▁used . ▁In ▁engineering ▁projects , ▁it ▁had ▁the ▁advantage ▁that ▁transport ing ▁the ▁bulk ▁materials ▁and ▁casting ▁them ▁near ▁the ▁place ▁of ▁use ▁was ▁che aper ▁than ▁transport ing ▁very ▁large ▁pieces ▁of ▁stone . ▁ ▁Modern ▁cast ▁stone ▁is ▁an ▁architect ural ▁concrete ▁building ▁unit ▁manufact ured ▁to ▁simulate ▁natural ▁cut ▁stone , ▁used ▁in ▁unit ▁m ason ry ▁applications . ▁Cast ▁stone ▁is ▁a ▁m ason ry ▁product ,