I thought you might be interested in this Ashmolean object: Pilaster on the unfinished Facade of Sant' Anastasia, Verona , http://ruskin.ashmolean.org/object/WA.RS.ED.093
Pilaster on the unfinished Facade of Sant' Anastasia, Verona John Ruskin
The drawing shows the upper section of two pilasters on the west facade of the church of Sant' Anastasia, Verona. These are: the pilaster on the left edge of the facade, where it joins onto the wall which supports the Castelbarco Tomb; in front of it, only partially drawn, is the pilaster immediately to the left of main portal. Both are made up of marbles and other stones of different colours, and the far pilaster is decoratd with foliate patterns in relief. They are drawn from above, and to the side: Taylor suggests Ruskin took advantage of the scaffold which had been erected by some workmen at the time he was working on the drawing. Taylor notes that Ruskin was drawing the facade on 26 and 27 May 1869. (The drawing of the lower sections of the pilasters, seen from the same angle, no. 68 in the Reference Series, seems to have drawn yhe following month.)
The present drawing was first catalogued in the Oxford collections in 1871, as no. 43 in Case IV of the Educational Series, which contained "Illustrations of Italian Gothic, with its resultant art"; as the Series was renumbered in 1874, it became no. 93, but remained in then same place.
Ruskin included both pilaster drawings in his Verona exhibition in February 1870, noting of the upper section that 'The purple and fine-grained white marbles of the pilaster are entirely uninjured in surface by three hundred years' exposure' (no. 39 = XIX.457), whilst the drawing of the lower section showed 'the effect of differently coloured marbles arranged in carefully unequal masses' (no. 40 = XIX.457). He also seems to have referred to them in his lecture on colour on 23 February 1871, noting that the areas of colour were 'edified', i.e. laid next to each other like stones in walls, rather than superimposed. They also showed how, by surrounding white paper with colour, its whiteness was intensified; and he remarked upon the absence of black in them. (Lectures on Landscape, §§ 72-3 = XXII.55.)
watercolour and bodycolour over graphite on paper, some lines ruled
Europe	› Italy › Veneto (Venetia)	› Verona › Verona	› Chiesa di Sant' Anastasia	› Chiesa di Sant' Anastasia (subject)
WA.RS.ED.093
pilaster
Taylor, Gerald, 'John Ruskin: A Catalogue of Drawings by John Ruskin in the Ashmolean Museum, Oxford', 7 fascicles, 1998, Oxford, Ashmolean Museum, no. no. 108
Ruskin, John, 'Lectures on Landscape: Delivered at Oxford in Lent Term, 1871', Edward T. Cook and Alexander Wedderburn, eds, The Works of John Ruskin: Library Edition, 39 (London: George Allen, 1903-1912), 22
43 Pilaster of unfinished façade of the Church of St. Anastasia, Verona. M
93.	Pilaster of unfinished façade of the Church of St. Anastasia, Verona. M