In article ,
"Andrew Mawson" writes:

During the Rhodesia crissis ( UDI etc 1965 onwards) aluminium was used in
house wiring due to copper shortages - dreadful stuff - breaks easily at
screw terminals. During the same period stainless steel was being used for
plumbing.

OTOH are you sure that you haven't come across a bit of the old 7/029 used
around then - seven strands of 29 thou copper that was usually tin plated -
this was a pre-metrication standard.

Personally, I've only ever seen solid cored aluminium T&E.
7-stranded, if it ever existed, sounds like real recipe for
aluminium connection/oxide/fire disaster.

--
Andrew Gabriel