Bartolomeo Colleoni, after Andrea del Verrocchio

Charcoal on paper

Graphite and white gouache on greenish-gray prepared white wove paper

Brown ink on thin ivory wove paper

Watercolor and graphite on paper, adhered to wood board

Graphite on buff wove paper

Graphite on blue-flecked gray laid paper

Charcoal and white chalk on buff wove paper

Watercolor and white gouache over graphite on heavy beige wove paper

Graphite on off-white wove paper

Gray wash with touches of red watercolor on off-white wove paper

Watercolor and white gouache over graphite on off-white wove paper

Brown ink on ivory wove paper