Are those the only picks you use? Who made them for you?
For my acoustics, I normally use a 1.3mm Brain pick, or Cat's Tongue.
The silver ones are my go-to picks for electric guitar and mandolin, I use them occasionally on my acoustic guitars. Of course, metal expands when warmed, so these picks take on a unique tone when they're all warmed up.
The quarter dollar pick is from my birth year and the half dollar is the last year of the silver coins. I also have two older half dollar picks, a Walking Liberty and a Franklin.
You can find them for sale on line, but their price has increased significantly from when I bought mine a few years ago. If you but one, be sure it is a vintage 90% silver one, i.e., 1964 or older.