This antique mortise door lock assembly is a model No. 50 manufactured by the Reading Hardware Company of Reading, Pennsylvania. The set is constructed from cast copper-alloy, likely brass or bronze, and features two egg-shaped knobs on a threaded spindle with one circular rose plate. The lock box displays the horizontal characters No 50 and the vertical manufacturer name READING. This style of builders hardware is typical of the late 19th to early 20th century in America, commonly associated with Victorian and Colonial Revival architectural styles. The entire assembly exhibits a heavy, naturally aged verdigris patina with mottled greenish-brown oxidation. The latch bolt is present and extended. A paper identification tag is currently attached to the unit with a white string.