The slate slipped immediately above a group of workers, who raised the alarm and ran for the outside.

[2] On 12 December 1866, the quarry's owners, Messrs. Brett and Capper, were granted sequestration by the Court of Chancery against Cambrian Railways.

This was due to the work on the "Glandyfi diversion" section of the Cambrian Coast Line,[3][4] which has a bridge over the former route to the Frongoch Harbour, from the quarry.

The quarry and associated land was under a lease from Mr. James Hughes[5][6] (the owner of the Frongoch Farm),[8][9] expiring in 1910, for a nominal royalty; the Frongoch Harbour on the River Dovey (which the quarry used) was under a Crown lease for £2-per-annum (equivalent to £251-per-annum in 2023).

[13] The quarry, harbour, tramway, and associated buildings were first advertised for sale, by private treaty, on 19 November 1880.

[14][15] On 27 August 1886, at 3:00pm, the Frongoch Farm, on whose land the quarry lay on, was auctioned by Mr. Owen Daniel.