Yes this is 1 Tangka coin from Tibet.
The Obverse shows a single wavy water line between petals and the Reverse has 3 dots between petals, hence it is of Type E.
Don't know if its Y#E13.1or Y#E13.2 as my edition of Krause catalog does not have pictures for them.
But if you refer the article "The Gaden Tangka of Tibet" by N. G. Rhodes (which is available at
http://www.onsnumis.org/articles to download), it seems to be Type E(iv)
You can also refer to examples of various types
here on zeno.ru
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