Size range from one-fourth plate and are often datable by the Potter's Patent paper holders, adorned with patriotic stars and emblems, that were introduced during the period.
After 1863 the paper holders were embossed rather than printed. During this period "rustic" photography also made its debut with its painted backgrounds, fake stones, wood fences and rural props.
Later, cabinet styles would become more ornate and as the carte de visite waned, the cabinet card would set the style for the carte.
Therefore, cabinet card styles can be used to approximate a date for an unknown cabinet card.
The styles of later cartes de visite of known date should be used as a guide to dating the cabinet card.
The Cd V styles in all likelihood tracked somewhat behind those introduced for cabinet stock each year.
There has not been as much research on the cabinet card styles as on the carte de visite styles, therefore they may be more difficult to assess.
But like the Cd V, the an approximate date for a cabinet image should be obtainable through an understanding of it's features.
Early on, imprints were simply one or tow lines giving the name and location of the photographer.
Later imprints show a great variety and richness of ornamentation.
Note that dating the mount does not necessarily date the image.
The photographer may have been using up old card stock.
Trends in imprint styles can help approximate a date. Internal Revenue stamp can date the image to the period to (roughly the end of the American Civil War to the introduction of the cabinet card; I think it would be rare to find a cabinet portrait bearing a tax stamp).