Coloral alloy cages go back to the '40s I think. They were anodized in colors too, like gold, blue, green and red. Thus the name, Color-Al. British made I think.
I first saw TA alloy cages maybe about '75, not at all sure of that. Certainly by '77-78 when I first bought some. They eventually became popular and spawned lots of imitators. Came in black or silver ano. The black ones with their gold plastic clip at the top proclaimed to the whole world that you had spent the extra $$ to save a little weight. Silver was a bit more discreet. The band clamps and even the bolts holding the clamps shut were alloy. Nice exotic bolts that were unfortunately not very useful since (eventually) most better frames had braze-ons. I still have a little pile of those alloy bolts, can't figure out what to use them for.
True of any Al alloy cage that I know of: The ano wears off the cage rapidly, and then that blackish oxidized aluminum stains all your light colored bottles, and doesn't wash off. I know bike bidons are meant to be expendable, but some have sentimental attachment like my '70s TA with the cartoon character, Red Zinger or other race bottles, early Fat Tire Bike Week etc. I eventually went back to chrome-plated steel TA cages on some bikes just to avoid the alloy stain. Stainless steel (or titanium) is a no-brainer, but no one made them BITD, that I can recall, alas. Plastic or CFRP get the job done but I'd rather die than put one on a vintage bike!
Mark B