"Burmah-Shell" was a joint-venture oil company, between British-based Burmah Oil and Dutch-based Shell Oil, which traded in colonial and post-independence India. In 1976, the Indian government purchased and nationalized the company, which became Bharat Petroleum. The company still traded in Pakistan as Pakistan Burmah Shell until Shell took over complete operations in 1993.
So presumably these medals are Indian in origin, and presumably from the 1960's or early 1970's.
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis