Watch List notes:

Constantine X Ducas, 1059-1067. Histamenon circa 1059-1067, AV 4.40 g. Christ, nimbate, seated facing on lyre-backed throne, raising r. hand in benediction and holding book of Gospels. Rev. Emperor standing l., wearing crown with cross and pendilia and loros, placing r. hand on chest and holding globus surmounted by pelleted cross with l., blessed by Virgin, nimbate and veiled, standing beside him; between their heads, M and in upper r. field, Θ. DO 2. Sear 1848.
Insignificant marks on obverse, otherwise extremely fine

Ex Glendining's sale 5 March 1980, 76.