This "paste-up" model for the 90c 1869 issue is composed of a vignette of Lincoln, cut from a proof of the15c 1866 issue, and pasted into the center of a navy blue, small-numeral frame essay. 

Frame-only essays, as well as bi-color essays with a vignette of Washington (printed in black) were prepared from plates of 50 subjects. While blue frames are known for both frame-only and bi-color essays, the navy blue color of this frame seems to be particular to the paste-up models. Click here to view these essays. 

Two other frame colors are known for these models, yellow and blue-green. If we speculate that, similar to the way in which the Washington-head essays were prepared, entire sheets of 50 models in these three colors were produced for approval purposes, then 150 such models should exist. Surely, it would have taken a significant amount of time to prepare this many models; a sheet of the 15c proof would have had to be printed and cut up; sheets of the frame-only essays would have to be printed in a variety of colors and color-evaluated; the vignettes would then have to be carefully pasted, individually, to each 90c frame. These models were considered by Brazer to be rare, and it is likely that many fewer than 50 of each color exist. The Scott catalog price reflects their rarity. 

The image at bottom illustrates how a portion of the crosshatching originating in the 15c proof was not completely removed when the vignette was prepared for this model.