Private Owner and Railway Company Liveries.
Following the railways 'grouping' forming the many British railway companies into four large regional companies the Railways Clearing House issued a through overhaul of the wagon specifications. The 1923 mineral wagon was longer than the earlier designs at 16ft6in. and oil lubricated axleboxes were required. Several thousands of wagons to this design were built by the LMS and LNER as their standard mineral wagon types along with many more for private owners and, with many wagons 1923 specifications wagons still less than 25 years old at nationalisation, these ran into the late 1950s with British Railways.