Lot 30101 – 1913 Romanov Tercentenary 70k purple and brown complete proof on chalk surfaced paper

1913 Romanov Tercentenary 70k purple and brown complete proof on chalk surfaced paper, with the names of designer and engraver beneath the picture. Possibly from Tsar collection R. Lowe 1935 as described published in the Yamschik-Postal Rider 1983, No 12 page 15.