St Matthew's, in Caversham bluestone with unusual Port Chalmers stone dressings, is a large church, of strong design, very English in feeling, with aisles and octagonal piers. It is a contrast to All Saints and reflects a return to convention in English church design. Before it was completed Mason's wife Sarah died, on 22 September 1873. On 20 December that year he married Catherine Fenn, a widow thirty years his junior. Mason was still designing, completing the Otepopo Presbyterian church and the Standard Insurance Company's office in Princes Street (the Clarion building), in 1874, both of which survive. He then dissolved his partnership with Wales, after which he may have visited England.