Covering the period 1390-1488, MacKay publishes the second portion of the Lord Stewartby Collection, the most important collection of Scottish coins ever put together by a private individual. Shortly before his death in March 2018, the collection was gifted to The Hunterian at the University of Glasgow. Comprising 5000 coins, the collection was formed between c. 1950 and c. 2010 by Ian Stewart, a banker and later a politician, initially as a Member of Parliament 1974-92 and from 1992 sitting in the House of Lords as Lord Stewartby. He was a highly regarded numismatist and the foremost scholar of Scottish coins in his generation. This exceptional collection has a depth and range across all metals and denominations which make it an important academic resource for researchers, whether numismatists or historians, or as a reference point for collectors.

The Lord Stewartby Collection is the finest collection of Scottish coins ever assembled by a private individual. MacKay details over 1080 coins of all metals and denominations issued between 1390 and 1488, when Scotland battled to maintain a competitive currency but also a time of innovation and orginality.