GOVERNMENT (BLUE BACK)
When NJ converted from the blue plates to the graphic plates in 1991/1992, there were some unused blue plate blanks left over.
Reflective sheeting was applied to the blue blanks, so we have some reflective plates with a blue painted back.
MUNICIPAL
MG19660 has an unpainted aluminum back.
At some point before MG21865, the blue back plates appeared.
Phil Leib

Phil Leib

Jon Cohen

Jon Cohen


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The blue backs probably stopped at the changeover to the Avery base, around MG51000.
(MG56102 verified with an aluminum back.)
COUNTY GOVT
7-digit CG plates up to CG20853 had unpainted aluminum backs.
The blue back CG plates probably started at E100-CG, coinciding with the change back to 6-digit numbering.

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The blue backs probably stopped at the changeover to the Avery base, at L100-CG.
(L892-CG verified with an aluminum back.)
STATE GOVT
Early 7-digit SG plates all had unpainted aluminum backs. (SG12104 is the highest verified.)
The blue backs may have started around SG13000.




The blue backs probably stopped at the changeover to the Avery base, around SG23000.
(SG25462 verified with an aluminum back.)