Told you stone has a future !
Post tension stone work well, really well ! http://www.architectsjournal.co.uk/news/cost-of-portcullis-house-repairs-go-through-the-roof/8674535.article?blocktitle=Daily-news&contentID=7303 on this project the stone column not wet cast, not concrete. Sandstone, post tensioned on site, so the slick and solidity aspect are well in place ! Michael Hopkins practice did very well and the solidity of the stone can not be dismissed !