I have a 120 x 120 matrix like so:

50220 12200 40220 51211 60300 11120
50230 12210 40220 51211 60302 11122
50231 12220 40221 51220 60305 11130
50232 12220 40224 51220 60305 11130
53100 15010 41000 51221 60320 11212
53101 15010 41000 51231 60322 11222
53202 15020 41004 51310 60401 11230
53202 15020 41020 51310 60421 11230
53220 15100 41204 51311 60422 11230
53221 15100 41220 51330 60425 11232
54100 15110 42001 52111 61000 12110
54131 15110 42020 52121 61002 12130

....and so forth.

Is there anyway to highlight all values that are duplicated? Some values
have lots of duplicates; others have only one. I'm not looking to eliminate
the duplicates, just being able to recognize them visually.

Thanks yet again.