from Fancyclopedia 2 ca. 1959
Reproduction by adhesion of ink to prepared surfaces; metal sheets are used nowadays (stone was the original surface, hence the name) which can reproduce in accurate detail and with large solid areas; photos can be reproduced in half-tone. The process came into considerable use with Assorted Services, tho presently commercials were found who could do the job cheaper than Ackerman & Co. (It costs plenty anyway.) Our front cover [in first ed] is an example of this process.