Fig. 2

a Twelth century Wardrobe Tower, Tower of London, showing decayed, south facing Reigate Stone ashlar in upper part of buttress and to left of buttress. b Eleventh century White Tower, Tower of London with east facing Reigate Stone ashlar visible in two courses directly above batter, and predominantly Portland Stone replacements. c Reigate Stone tracery from eleventh century Merton Priory on display in Museum of London. d Reigate Stone tracery in sixteenth century north cloister of Hampton Court Palace. e Large blocks of stone left in quarry near Chaldon (scale card is 8 cm across). f Quarry face near Merstham from which samples were extracted in 1998