Hidden high security feature - an additional security feature is built into the coin to protect it from counterfeiting but details have not been revealed.
So, security by obscurity. I wonder how long that will last.
http://www.huffingtonpost.co.uk/entry/new-pound-coin_uk_5818...
http://www.gizmodo.co.uk/2014/03/what-is-the-new-1-coins-isi...
Hidden high security feature - an additional security feature is built into the coin to protect it from counterfeiting but details have not been revealed.
So, security by obscurity. I wonder how long that will last.