The completed grisaille (monochrome underpainting).
Glazes (diluted oil paint) added to approximate regions of flesh tones.  I've already added some color to the coat and tie at this point. 

Carefully wiping glazes down to reveal underpainting.  The glaze adds color to the dark and light.  

A black glaze over the background and the coat mellow out those areas.  Time to let the painting rest for a while as the glazes dry.
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