Tamlat, otherwise known as Tamlaght or Drumfaldra, occurs in the townland
of Aghnamullen, by which name a clay and lead ore mine was worked as early
as about 1750. The mine was apparently operated for a brief period by
the Johnson family in the mid-18th Century. A surface plan of the mine
workings in the Geological Survey of Ireland, though undated, probably
dates from about 1880, and shows a series of pits, trenches and shafts
aligned along a bifurcating lode over a distance of about 1,000 feet.
There is now no visible evidence of any of these workings.