Well I am damned, I never knew they made an Aden in 25mm...I was all set to flame someone there!!
It appears the thing never went into production.
Oddly, this may have answered me a question as I have something very similar in 25mm, but a TP round with a green steel case. It is pristine but the primer has been removed to the powder woudl have gone that way. certainly would explain why it was done to a brand new round.
I have examples of the 30mm Aden and the M778 (TP) round used on the AH64...oddly the same.
A nice thing to have for a good cause.