BUILDING STONE 333 related to lithology, conditions of origin, and geological history (Table 3) and are reflected in mineralogy and petrography, and include fabric and texture Large expenditure on the acquisition of building stone should include a petrographical analysis for the latter features Locating Sources of Building Stone Building stone has a relatively low economic value in the outcrop, its true value accruing from its placement work by stone mason tradesmen Its recovery is expensive in terms of specialized skills and by the judicious use of explosives and of construction machinery for its recovery A number of factors related to prospecting for building stone deposits are well suited to engineering geological training (Table 4) Environmental Planning for Recovery of Building Stone As with most earth materials, there are two levels of activity that apply to recovery of building stone, informal and formal For all but the weekend mason, all other recovery activities quickly will be recognized by environmental regulatory authorities as a form of ‘quarrying’, for which even a small stone recovery enterprise will require submittal of a Permit Application and some scheme of site development and integrated measures for protection of the environment (Tables and 6) Stone Masonry Modern stone masonry nearly always serves the aesthetic purpose of the architect or landscape designer No longer are we concerned with use of stone for its original structural role, but the manner in which the masonry is placed provides ample opportunity for meaningful artistic statement (Table 5) Petrography Petrographical examination of thin-sectioned hand specimens recovered from prospecting will be helpful in some instances in which the shape, colour, and/or texture meets the client’s approval, but the geologist remains wary of the ability of the stone to meet expectations when placed in exterior locations exposed to the elements As with basic identification of the stone, such manuals as listed in the Further Reading Section below provide an excellent desk reference Summary Building stone provides a durable, aesthetically pleasing construction material where wear-resistant and climate-resistant natural stone can be used to enhance the qualities of modern construction Significant costs must be paid for accessing and recovery machinery, palleting, and transportation to the vendor’s yard Application of geological knowledge is essential to providing appropriate attractive and durable stone at an economic production cost See Also Aggregates Engineering Geology: Rock Properties and Their Assessment; Site and Ground Investigation Further Reading Bates RL (1987) Stone, Clay, Glass; How Building Mater ials are Found and Used: Enslow Bell FG (1993) Engineering Geology: Oxford: Blackwell Scientific Publications Blyth FGH and de Freitas MH (1984) A Geology for Engineers, 7th edn New York: Elsevier Geological Society of London (1999) Stone; Building Stone, Rock Fill and Amourstone in Construction Engineering Geology Special Publications 16: 480 Parsons and David (eds.) (1990) Stone; Quarrying and Building in England London: Phillmore, in Association with The Royal Architectural Institute Shadman A (1996) Stone; An Introduction London: Inter mediate Technical Publications Smith MR and Collis L (eds.) (1993) Aggregates; Sand, Gravel and Crushed Rock Aggregates for Construction Purposes, 2nd edn London: Geological Society Special Publication no 9, p 339