Just now seeing this thread, there was hints of blue paint on the ones I took off of my 79 Tenth.
Thanks Kerry. I had cleaned these all up with a wire brush on a drill 20 years ago before painting the lot silver. So many finer details or surface plating was lost. But after stripping the paint off recently any that were different colours were still tinted or had patches visible.
One thing clear was that regardless, all were plated silver first. I had a few of the same type that had a strong orange tint, mainly inside where protected. While it seemed a little brighter than old gold plating that's what I did to them anyway. And I had a few others that were black. None were obviously blue but the reproduction types and even one of the Assembly manuals does reference a blue. Blue over black or blue over silver plating, not sure. I've found a few photos of other vehicle at same time that showed black clips. There were also several variations in sizes in my lot so may have been more long worn away.
I took photos of every clamp before, during and after, locations and details of each so they go back in the same spot. Obsessive, yes. Here's one after paint stripping that shows the black, inside and out, also the bare metal vs the brighter and lighter plating. Any that were black were all the same type and size.
Firebird RH Rear fuel brake line clips removed R-F 1st not removed Black 2 (3) by
Ben, on Flickr
I have a few saved pics of original or low-mileage cars but few show anything clearly. This one is 79 Formula W72, and clearly shows the same type of black clip but wearing around the edges.
79 400 Formula original low miles (4) diff exhaust brakes by
Ben, on Flickr
Some of the reproduction clips in blue, originally aimed at 68-72 era vehicles, are almost how we know blue anodising as, clear over silver plating. I found a few repro sets that do theirs as a flat paint/teflon coating. Possibly the same brand, it appears they do the smallest, single line clamp as blue. I'll have to check my pics and the diagram that mentioned it.
https://www.inlinetube.com/products/ccb208https://cdn2.bigcommerce.com/server2400/nqdzgu/products/982/images/1055/%252521Bn51mQw%252521mk~%252524%252528KGrHqMOKi8EtlYz2MYIBLlWj16Pg~~_1_884_1__61199.1353280169.380.380.JPG?c=2I'm not sure what to make of this one, lousy pic of a low-mileage 79 Formula. Appears to be more of an inspection dab of sky blue paint, over clip and bolt, even the leafspring cradle bolt. But a very different blue if you were seeing remains like that.
79 400 W72 unrestored fuel lines evap and return by
Ben, on Flickr
Same again for a few that showed hints of a dark orange plating, mainly inside. Far more obvious than the plain type and lost somewhat with the flash. They showed up coppery from different angles. The light grey here under it is the silver plating, bare metal around edges where I've scratched off. There were 3 of this type. Prior to being sent I'd soaked them in chemicals to take right down to bare metal even though the plating guy does also.
Firebird centre fuel line clips orange gold (3) by
Ben, on Flickr
Here's a pic of an original 'museum' 78. The clamp appears to be a dull and faded gold plating. I'll have to check if that's also where one of mine was.
1978 TA unrestored brake fuel lines2 by
Ben, on Flickr