Please Advise - New To Stamps, Just Found A Half Pence Used In Great Condition George V Stamp.

Just found this stamp in an old book - would anyone know it's approximate worth?

Seems to be a green Henry V stamp with a tangier mark post office on it.

That is a Great Britain stamp depicting King George V. It was issued to be used in Tangier, hence the overprint. I wouldn't call it "great" condition as there appears to be a poor lower left corner. Value in this condition is less than a dollar, but I would keep it on the paper, don't soak it off.

The stamp was overprinted for use at the British Post Office in the international port zone of Tangier. Since it was for use at the post office, there was no need to change the value. From memory, the four TANGIER stamps (Block Cypher watermark only) were issued in 1927. It was one of the Morocco Agencies.

Having readable cancellations for the BRITISH POST OFFICE TANGIER is a big plus. Used stamps only have value with a recognisable cancellation for the British Post Office in Tangier.

As Partime already remarked, it has condition issues. The curled lower left corner, in particular, is quite a problem. The sloppy manner in which the piece was torn from the entire is a negative. I am not sure if there is a fibre or large tear at lower right. It appears as if the lower right corner was severed from the stamp.

As for Henry V, he ruled more than five centuries before the stamp was issued. As Partime, already, remarked, it is King George V. The stamp is called a "Mackennal," or "Profile Head."

.... and a second stamp has been peeled-off, taking most of the upper cancel with it.