Rosalba Carriera [Public domain], via Wikimedia Commons.
This looks good. For those interested in pastel's historical development.
Pastel Portraits: Images of 18th-Century Europe
May 17, 2011–August 14, 2011
Brightly hued, highly finished, and relatively large in scale, pastels in the 18th century were regarded as a type of painting and displayed like oils. The powdery, vibrant crayons are particularly suited to capturing the skin tones and evanescent expressions...