The title pretty much says it all. I was confused for months because I didn't know what "non-selected trial strike" meant, and I think many other people were confused too. But suddenly, enlightenment dawned, and it made sense to me! "Trial strike" is self-explanatory... and "non-selected" means that there is no real coin that has the same composition or design as the trial strike, making the trial strike special and unique.
However... there is no need to use four words in this situation, because only one is needed: "pattern" (Wikipedia). This should make the catalog easier to use and edit, especially for new users.