I’ve become quite a fan of the Victorians/Edwardians in the course of this project, their fascination with science, building, innovation and categorisation. Less a fan of course of their racism, imperialism, colonialism, sexism, employment practices and their almost utter disinterest in protecting the environment of course! But you can’t have everything!
[ NB it is of course also a fact that all but subsistence building is based on a level of surplus value creation from one or other forms of exploitation. And the extraordinary buildings of all eras in London are all based on wealth from conquest, theft, poll taxes, imperialism, slavery and colonialism and the use of certain stones, Caen for the Normans and granites with the Victorians, to show that power in concrete built form. ]
So I got very excited when I heard that the The John Watson Building Stones Collection at the Sedgwick Museum in Cambridge still existed and was able to arrange a visit recently.
One of the big problems with learning about building stones and materials is that there are no recent general books so the Watson collection and the book that went with it is of immense value for learning the building stones I see around London. Watson’s book “British and foreign building stones, a descriptive catalogue of the specimens in the Sedgwick Museum, Cambridge” produced in 1911 is extraordinary. 240 pages of description of building stones used in the UK and then a numbered description of all the stones on display in the collection. I’ve had a PDF of the book for a while but a visit to the collection seemed essential!   Read a contemporary review here: “British and Foreign Building Stones. A Descriptive Catalogue of the Specimens in the Sedgwick Museum, Cambridge. By John Watson. George P. Merrill in Vol 34, Issue 877 Science 20 Oct 1911 p. 520. 
There are other incredibly good/useful bits and pieces for learning about building stone. The UCL walks of Ruth Siddall are brilliant though they cover lots of modern marbles and exotic stone I am not that interested in.   and of course the extraordinary London Pavement Geology Geo-sites maps, but it’s coverage of buildings is still limited. 
Eric Robinson, the godfather of urban geology, produced 2 seminal ‘London: Illustrated Geological Walks’ books in the 1980s, only 1 of which, Book Two, is freely available. 
The British Geological Society’s have some great ‘Holiday Geology Guides’, some covering urban geology , while their County Building Stone Atlases are also incredibly good but as yet Middlesex / London has not been produced as I imagine that this the hardest county to do!   Books on stone conservation are also really useful like The Conservation of Building and Decorative Stone by Ashurst and Dines.  And other towns and cities geology walks all help build knowledge e.g. Edinburgh!  and check out The Building Stones of Edinburgh which is brilliant.  and in Birmingham too. 
The Sedgwick Museum holds 2 million rocks and minerals but my interest is very specific to the Building Stones Collection. ” .. named after it’s donor, John Watson (1842-1918), who donated his collection of approximately 300 British and foreign stones and specimens illustrating the manufacture of plasters and cements to the Museum in 1905. Watson… continued to develop the collection until his death in 1918. Today it comprises approximately 2,500 traditional building stones, roofing slates, road stones, flagstones and decorative and ornamental stones that were in extensive use throughout Britain and it’s colonies during the 19th and early 20th centuries. ”  And it is as great as I imagined. Case after case of the stones we see around us everyday, but know nothing of their origin.
Watson’s obituary in 1918, after falling from a ladder I would like to hope examining some unusual building stone [actually he was pruning a Fig tree], states
“Disdaining a life of ease, he devoted his special knowledge and great energy to the acquisition of an unrivalled collection of building-stones, ornamental marbles, and other materials connected with building. These he presented to the Sedgwick Museum, and spent his leisure in arranging them and writing descriptive catalogues. Two of the catalogues have already been published, and are well known to geologists and to those connected with building, namely, British and Foreign Building Stones and British and Foreign Marbles and other Ornamental Stones. ” 
The Sedgwick Museum itself was opened in 1903 and named for Adam Sedgewick the early/mid 19thC geologist. A classic flawed Victorian: a geologist who took a while to accept modern geological theory but then accurately and painstakingly described the geology he observed, who was against the theory of evolution “…If .. [evolution] be true, the labours of sober induction are in vain; religion is a lie; human law is a mass of folly, and a base injustice; morality is moonshine;” who supported the abolition of slavery but was a slave owner, and who was also deeply sexist “He strongly opposed the admission of women to the University of Cambridge, in one conversation describing aspiring female students as “nasty forward minxes.” 
It’s full name is The Sedgwick Museum of Earth Sciences and it is the geology museum of the University of Cambridge, and “the oldest of the eight museums which make up the University of Cambridge Museums consortium..[with] a collection of around 2 million rocks, minerals and fossils, spanning a period of 4.5 billion years.”  
The collection was as I had imagined. Unchanged from the early 20thC, and like the museums I loved to visit as a child, with no interpretation but just case after wooden and varnished glass case stuffed with dead birds, butterflies and glass eyed otters! Tbh I would have walked right past these cabinets of stone then, entirely uninterested. Now I’m fascinated by their contents as they show us what is all around us.
The cabinets are so old that sadly 2 or 3 of them would not open as the wood had warped and as there is not much interest in the collection, the collection room now doubles up as the students and staff canteen and rest area, and indeed my visit was arranged outside of term time due to that.
The collection, while dusty and with some labels fading, is as complete as when Watson died and indeed has been added to as a review of the collection by Katherine J. Andrew of Birmingham Museum and Art Gallery showed in 1991, though sadly she noted the artificial stone collection, something also of fascination to myself, has apparently entirely disappeared. I have a number of posts planned on artificial stone. 
I spent several hours photographing but it was worth every second.
An absolutely amazing and indispensable resource
And finally. Just look at the stunningly beautiful writing on some of the labels!
I took a very large number of photos, 782, of varying success as the lighting was not great, but they are already being useful for me learning to identify stone and it’s sources and I’d like to thank Matt Riley at the Sedgwick very much for facilitating my visit!
Cambridge is an amazing place to see historic building stone, as being a wealthy city in Mediaeval times it was able to draw in stone from a wide range. Some of the stone there is also found in London and I have posts in the pipeline on Collyweston Slate and Barnack stone. And look out for urban geology walks in Cambridge led by Nigel Woodcock! This is an old one here  and this Cambridge Geology Trail leaflet from 2009 looks amazing but seems to be out of print 
Getting there from London:
Cambridge is relatively easy to get to from London by train. A day return from Kings X or Liverpool Street. The Sedgwick is on Downing Street off the main Road, St Andrews Road, up from the station. The Building Stone Collection is not open to the public though ordinarily. An appointment must be made.