Bell’s earliest pieces are paintings in the Abstract Expressionist tradition. He began incorporating fragments and shards of clear and mirrored glass into his compositions. At the same time, he began in his painting to produce angular geometric compositions that alluded to or represented three-dimensional forms. These works frequently depicted rectilinear forms with truncated corners. Next there came a series of shadow boxes or “ghost boxes”, three-dimensional cases whose surfaces often featured shapes reminiscent of those in the preceding paintings. Of this transition, critic Peter Frank has observed: