I have been working recently on various collections of illuminations, including that of R. S. Holford [
Wikipedia], attempting to trace the present whereabouts of each item.
In the course of tracing Holford's miniatures, I was reminded that he lent several to the 1862 International Exhibition [
Wikipedia] at the South Kensington Museum (now the V&A). The catalogue is available online through
Google Books and
Archive.org:
Catalogue of the Special Exhibition of Works of Art of the Mediæval, Renaissance, and More Recent Periods, on Loan at the South Kensington Museum, June 1862, edited by J.C. Robinson (revised edition: London, January 1863).
The Holford miniatures were catalogued in detail twice in 1927, each time with numerous reproductions, so we have a very good idea of its contents before dispersal:
Robert Benson, The Holford Collection, Dorchester House, with 200 Illustrations, from the Twelfth to the End of the Nineteenth Century, 2 vols (London: Humphrey Milford).
and
Sotheby & Co, The Holford Library, Part I: Catalogue of the Magnificent Series of Illuminations on Vellum, Forming Part of the Collections at Dorchester House, Park Lane, the Property of Lt.-Col. Sir George Holford, K.C.V.O. (Deceased) ... 12th of July, 1927.
In principle, therefore, it ought to be easy to identify items from the collection. In practice, however, it is not always so simple.