I agree that your best resource may be Mr. Fidler. I just wanted to share that several years ago, before digital camera, I visited Cranbrook Academy of Art in Michigan. You may recall that Eliel Saarinan lived and taught there for many years. The Academy is equipped with shops capable of creating many construction materials including metals and masonry. As an Art Academy they were constantly experimenting with masonry construction building a variety of facades, fences, niches, full building and their entry gate. I'm certain that I saw similar details in these masonry structures. The entry gate for instance has a construction date of 1927 and the medallions located to the right and left of the arch on both sides for the entry gate have thin pieces of masonry set in the center. I've attached one image scanned from a print. It illustrates one example of the masonry experiments. Other images may be found by just Googling Brickwork at Cranbrook Academy.As another option, and since Cranbrook also has an architecture curriculum, you may find shop drawings of their masonry experiments by contacting the Academy.
"Originally built for Genevieve Kassler and Sydney L. Brock, Jr., this 1928 home was designed by Merrill & Burnham Hoyt in the French Normandy style".