royal mine
(also mine royal) Law
noun
(In England and Wales) any gold or silver mine, especially one yielding more than will cover the cost of working.
- All such mines are liable to be claimed as the property of the Crown, under the provisions of 1 William & Mary c. 30, s. 4 (1688) and 5 & 6 William & Mary c. 6 (1693)..
Origin
Mid 16th century.