BHK Seal, Image & Found by Tadmark.
Found in North Yorkshire, 19mm.
BHK with inscription around (bottom half missing) ..JEVINA JUGOSL.. // (G?)UZNO curving downward / TAJERSK(I?) / ..INJSKA
Possible Yugoslavian origin. Other BHK seals appear to have the same writing on the BHK side but all differ on the reverse.
From Michel Royer, "Revers is : JUŽNO / ŠTAJERSKI / SAVINJSKA
JUŽNO = south
ŠTAJERSKI SAVINJSKA : region Styria Savinjska see : Savinja Statistical Region.
For moment I don't have solution for "BHK" but it is certainly official lead seal." Kingdom of Yugoslavia'The Kingdom of Yugoslavia (Serbo-Croatian: Kraljevina Jugoslavija / Краљевина Југославија; Slovene: Kraljevina Jugoslavija) was a state in Southeast and Central Europe that existed from 1918 until 1941, during the interwar period and beginning of World War II. From 1918 to 1929, it was officially called the Kingdom of Serbs, Croats and Slovenes (Serbo-Croatian: Kraljevina Srba, Hrvata i Slovenaca / Краљевина Срба, Хрвата и Словенаца; Slovene: Kraljevina Srbov, Hrvatov in Slovencev), but the term "Yugoslavia" (literally "Land of Southern Slavs") was its colloquial name due to its origins. The official name of the state was changed to "Kingdom of Yugoslavia" by King Alexander I on 3 October 1929.'