The lead version is depreciated in favor of the zinc, sometimes called terne II, and even that is not common in comparison to electroplating with zinc or another metal. Interestingly, terne is applied by painting the molten alloy. Tern the metal dates to at least the 16th century, though it was not a common word until terneplate was developed in the 1850s, and some dictionaries list it as a late 19th century back-formation from it. The root is unclear, but seems likely related to French terne, dull from Old French ternir, to tarnish, itself from the Germanic root that gave us tarnish by more direct pathways.
Heavens, it's an actual terneplate roof -- haven't seen one o' those for a while.
---L.