This is Haydarabad 1934 Sarkari
ovpt. on 1931 4P Sarkar I Asafiyyah
gray black official stamp (SG O46).
The unoverprinted base stamp (SG 41) with perf.13˝ was issued on November 12,1931, printed on unwatermarked wove paper in recess by Stamp Office, Haydarabad which also struck the Sarkari
overprint in Farsi in letterpress.
Vignette: It shows the Tu#287;ra emblem of Sarkar I Asafiyyah
i.e. Government of Asaf Jah VII, the official titular name of Usman Ali Khan Siddiqi (1886–1967), the ruler of Haydarabad (1911–1948) and the inscription Nishan I Tappah
i.e. Post Stamp written in Farsi below the Tu#287;ra.
The 1931 4P issue was printed from 10 different plates engraved by Thomas de la Rue and Company, London, England.
The plates were were extensively used simultaneously. Thus by 1942, the plates got worn out which resulted stamps with lighter impression, especially the central Tu#287;ra design which then did not have the characteristic background mesh.
There were several printing of this 4P value as it was required to pay the postage for letters i.e. 8P for 11.66gm (1 tola) (May 6,1930– December 1943) and 1A4P (December 1943–October 1949) and also to pay the registration fee 2A4P (1935–43).
So several color shades of black are found in these 4P stamps resulted from different ink batches having different tinge used in different printings.
Details can be found in, Haydarabad Philatelic History.
Muhammad Abd an Nayim Siddiqi.
Philatelic Congress of India, New Dilli 1980
Part III: Postage Stamps
Chapter 9(A): Postage Stamps; pp.185-92
Chapter 9(B): Sarkari (Official) Stamps; pp.213-7