Black Irish Tartan?

[mudd]

If you go to USA KILTS web site and look at the tartans available for the Casual Kilts, you will see one called “Shamrock”. Could this be what your friend called Black Irish?
http://www.usakilts.com/tartans/shamrock.jpg

http://www.usakilts.com/tartans/blackwatch.jpg

[Sir Robert]

I say introduce the kid to X-marks and let him figgure it out for himself.

[MACKAY]

I jokingly refer to my SWK Black on Black Tartan as my "Black Irish" kilt. I also know that there is a band called 'Black Irish'.

Brian