A cover sent from the Russian post office in Ulankom, Mongolia in 1917 sold for $232,207 at Spink Hong Kong on January 18, an increase of 157.3% on a $90,231 estimate.
The lot is the only item of mail sent from this post office, which was opened for a few short weeks prior to the October Revolution.
It bears a pair of 7k arms alongside an "Ulankom in Mongolia" circular date stamp.
It's described by Spink as: "a fabulous and highly important item of Mongolian postal history."
A block of four King George V requisition numbers also sold well, achieving $20,640.
Issued between 1934 and 1935, the design is printed on an olive green backing displaying the reference number N038.
An 1885-1888 small dragons cover sent from Newchwang (now known as Yingkou) to Kent, UK made $18,060.
The letter was posted on March 12, 1890 and arrived on April 28, having travelled via sea and across central and eastern Europe.
In addition to the small dragons, a France 25c is also included.
The cover remains in exceptional condition in spite of its age, displaying only some minor soiling to the flap of the envelope.
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