Standard degree certificates for all Colleges look the same, and are (to me) surprisingly plain and simple, although of course the design of the certificates has changed every few decades. There is no coloured ink on standard degree certificates, apart from on the University shield on newer certificates. Original certificates are issued are issued without charge to all persons proceeding to degrees. There is also a fancier, larger alternative design certificate with coloured ink, which is available for a fee, though I don't know what year these were introduced.
The wording and general layout on the certificate for academic degrees gained by completing a degree course at the University,
whether standard or alternative design, is:
[FULL NAME IN CAPITAL LETTERS]
of CHURCHILL COLLEGE
in the University of Cambridge
was at a full Congregation holden in
the Senate-House on
admitted to the degree of
[TITLE OF DEGREE] (BACHELOR OF ARTS, for example)
Witness my hand this twenty-eigth day of June, one thousand nine hundred and sixty-seven
[signatures of the Degree Registery of the University on the right, and the Registery's Clerk slightly lower on the left.]
If you wish to verify the authenticity of a certificate, I am sure you can contact the University - you can find information and links here: http://www.cam.ac.uk/univ /degree.