Poor Quality Chrome
Oof, nickle! Forgot that. The stuff on the caps is not the product, its probably 'vacuum metalizing'. Plastic is painted in a primer, then put into a vacuum chamber with a little piece of pure aluminum. then the AL gets vaporized with a laser or some other high heat process and the AL vapor settles on the (turning) plastic sprue or part. Pretty easy and very uniform. Mirror backs are plated with AL like this. There arre some artist pens called Molotow that comes in "Liquid Chrome" pens and refills that can be shot with an airbrush. Scale modelers may be familiar with it for 'chroming' small parts, ie. headlight bezels and antennas.
Oof, nickle! Forgot that. The stuff on the caps is not the product, its probably 'vacuum metalizing'. Plastic is painted in a primer, then put into a vacuum chamber with a little piece of pure aluminum. then the AL gets vaporized with a laser or some other high heat process and the AL vapor settles on the (turning) plastic sprue or part. Pretty easy and very uniform. Mirror backs are plated with AL like this. There arre some artist pens called Molotow that comes in "Liquid Chrome" pens and refills that can be shot with an airbrush. Scale modelers may be familiar with it for 'chroming' small parts, ie. headlight bezels and antennas.