Burke's General Armory, an old but authoritative resource on heraldic symbols and language gives the following verbal description of the Colvin family crest and coat of arms:
Side Note: I recently found that the crest and coat of arms shown above may be of Irish origin. Some references point to the coat of arms shown below to be of Scottish origin. However, I haven't confirmed this at this time. - R. Colvin, 04 September 2002

During this research, it has come to my attention that the following Clan Badge (or Clan Crest) was given to a member of the Colvin Family. I have not confirmed this at this time. - R. Colvin 08 October 2002

The best translation I can come up with for "Oublier Ne Puis" is that it is French for "I will not forget". That follows the family mottos Michael Colvin has on his site.
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