Just into Devon, coming from London, on the south coast, is the small seaside town of Beer. Building stone has been quarried below and above ground here since Roman times. And it makes a few appearances in building London.
Like Totternhoe [ see previous post ] it’s a chalk, this time a bit younger and from the Middle not Lower Chalk of the Cretaceous, and again harder than all the rest of the chalks and many older Limestones. It is some 50 million years younger than the Portland stone from not so far up the coast! 
I visited Beer in July in 2021 and had a tour of the old mine/underground quarry or caverns, which I would very much recommend!
Geologically Beer Stone is “An unusually hard part of the Middle Chalk ..[ that ] has been quarried in Hooken Cliff Landslip .. and much more extensively in inland quarries… The rock is a grey calcarenite, or shell-debris limestone, … In general terms it is a winnowed Chalk calcarenite on a submarine high, and .. it also resembles to some extent the Tottenhoe Stone [see previous post ] (although this has a different, finer-grained, petrographic fabric) ..” 
And “Beer Stone is a gritty-textured, bioturbated calcareous freestone which occurs near the base of the Upper Cretaceous White Chalk Sub-Group (Turonian age). It is known only from quarries 1.5km NW of the coastal village of Beer in SE Devon. The gritty texture of Beer Stone is not due to the presence of angular quartz sand, it is a chalky calcarenite comprising bivalve fragments, foraminifera and echinoderm debris. The stone is white to pale cream-coloured (buff) when fresh, becoming grey on exposure.” 
“The name ‘Beer Stone’ applies to a development of hard, homogeneous, white or pale cream coloured chalk occurring within the Holywell Nodular Chalk Formation at the base of the local Chalk Group succession. It is particularly suitable for use as ‘freestone’. When freshly quarried the stone is soft and easily sawn and shaped, but it hardens on exposure to the air. The beds are around 5 m in thickness and the stone has been worked both in
surface quarries and underground. When used externally, it tends to suffer from ‘flaking’, but because of its general characteristics, it was much sought after and used for decorative work.” 
The stone has been quarried from Roman times.    and different periods of quarrying can be ascertained by different styles of arches and roof supports [ as illustrated on the tour ] and by archaeological evidence such as a find of a Roman coin of the First Century AD  though the peak appears to have been ion the mediaeval period. The differences in styles can be seen on the tours of the Beer Quarry caves.
Use in London
Beer Stone was used in the mediaeval period in London for building though mainly for decorative work such as window jambs and screens. 
F G Dimes in ” The stone has been worked at Beer, Devon, apparently since Roman times; a ‘Roman quarry’ existed in 1932. It was also quarried in Hooken Cliffe, west of Beer Head. It was worked from open quarries until the overburden of other Chalk beds became too great. Tunnels were then made to extract the stone. The Beer freestone bed is up to thirteen feet (4 m) thick. It hardens considerably on exposure ‘and is altogether much stronger than Bath Stone and very much superior to Caen Stone which was once so much used in England …Chalk with no certain provenance but probably from Beer, Devon is noted for its use in St Stephens’ Chapel, Westminster, London and in the crypt of Lambeth Palace, London. ” 
The big advantage Beer had over other stones was that Beer was on the sea with a wide beach where boats/barges could simply be pulled up. And like with the importation of Caen stone to London, water transport was far superior to overland: “The recorded story of Beer Stone is of its diffusion, its mobility (by sea) – Beer stone recorded on masons’ stock rolls at London Bridge (1350), Rochester Castle (1368) and Westminster Abbey (early 1400s), the result of impressive networks of supply.” 
Beer Stone was much used in The Tower of London in the 14thC.
“Documents record the bringing in, in 1349, of Beer Stone (100 great stones, of which 50 were worked as voussoirs for the heads of doors and windows) …to the Tower in a dung boat .”  and 
Other references include – “Beer stone (a fine chalk from Seaton, Devon) was bought for an unspecified municipal purpose in 1350”  , “The Beer Stone has been quarried for age .. It ..can also be seen in St Stephen’s Crypt, Houses of Parliament, London.”  and “Beer Stone, from the village of Beer on the south coast of Devonshire, is a very compact white limestone, and a little harder than chalk. It has been quarried since Norman times and therefore has, to some extent, been drawn upon for service in London. It is suitable for fine carving, also for the ribs and webs of vaulting and other internal work. It is said to have been used in St. Stephen’s crypt at the Houses of Parliament, in the cloisters at Westminster Abbey, and in St. Paul’s Cathedral, and is mentioned in the Westminster Abbey accounts for 1413 as having been purchased with other stone for the rebuilding of the Nave.” 
The crypt under Parliament is one of the oldest buildings in London, finished in 1297, though after a fire in 1834 the crypt was apparently much restored and painted so I’m not clear if it’s possible to see Beer Stone in situ there. 
Seeing Beer Stone in London is fairly hard but the best example is in the vaulting of a ceiling in the Cradle Tower at the Tower of London. See above. 
I also love to see evidence of the workers and the caverns have lots of graffiti made by them, though to be fair these could have been tourists or even … smugglers! The famous Devon smuggler Jack Rattenbury used caves in Beer to hide his smuggled contraband! 
Beer is a fantastic place to visit just for the beach and the surrounding area is full of fascinating features whether geological or scenic.   The caves tour is £10 but it is well worth it and I say that as someone who likes his geology and history free! 
For a general and geological introduction to Beer and the surrounding area this, by Ian West, is brilliant! https://wessexcoastgeology.soton.ac.uk/Beer.htm
The 630 mile South West Coast Path from Minehead to Poole goes through Beer 
Check this for a good OS map https://www.southwestcoastpath.org.uk/print-walk/12/
The nearest train stations are at Axminster and Honiton out of Waterloo, on the rather slow West of England Line, taking c3 hours and then a 45 minute bus journey to Beer.
Cycling from Axminster or Honiton is c1hr and the cycle from Honiton goes right past the Beer Quarry Caves.
Driving; Beer is 3.5 hours from Waterloo via the A3/M3/A31/A35/A3052 or a more northerly A303 route.
 https://www.bgs.ac.uk/discovering-geology/fossils-and-geological-time/geological-timechart/  https://wessexcoastgeology.soton.ac.uk/Beer.htm  https://www.dorsetbuildingstone.org/beer-stone—se-devon.html
 http://www.beerquarrycaves.co.uk/beer-stone/  http://www.bbc.co.uk/ahistoryoftheworld/objects/4L9e0TfkT7WvgCSeOE0fDw  Medieval building stone at the Tower of London Tim Tatton-Brown https://www.yumpu.com/en/document/view/11957881/medieval-building-stone-at-the-tower-of-london  Conservation of Building and Decorative Stone John Ashurst and Francis Dimes 1991
 https://lukebennett13.wordpress.com/2014/04/18/gazing-up-looking-down-following-cathedral-stone-back-to-its-source/  Ruth Siddall / UCL https://www.ucl.ac.uk/~ucfbrxs/Homepage/walks/Eastcheap.pdf  The Construction of Medieval and Tudor Houses in London John Scofield https://www.arct.cam.ac.uk/system/files/documents/article1_6.pdf
 British And Foreign Building Stones: A Descriptive Catalogue Of The Specimens In The Sedgwick Museum, Cambridge John Watson 1911 https://archive.org/stream/britishforeignbu00watsrich/britishforeignbu00watsrich_djvu.txt  An Inventory of the Historical Monuments in London, Volume 5, East London https://www.british-history.ac.uk/rchme/london/vol5  https://www.british-history.ac.uk/rchme/london/vol2/pp99-148  https://thelanguageofstone.blogspot.com/2018/02/a-walk-around-walls.html  https://en.wikipedia.org/wiki/Beer,_Devon  https://www.southwestcoastpath.org.uk/walk-coast-path/south-west-coast-path-national-trail/
 http://beervillageheritage.org.uk.websitebuilder.prositehosting.co.uk/beer-history  https://en.wikipedia.org/wiki/Jack_Rattenbury