A gold color metal and enamel device 1 1/8 inches (2.86 cm) in height consisting of a blue ring divided by gold lines into eleven equal segments separated at right center by a white disc, the ring enclosing a stylized plumb bob divided vertically with white at left and scarlet at right and having a gold triangle-shaped aperture at top center.
Scarlet and white are the colors used for the Corps of Engineers. The plumb bob and the masoned ring (suggesting a fortification), are symbolic of Engineer functions. The blue of the ring (signifying water), and the white disc simulating a pearl, together allude to the Pearl River which flows by Monticello, Mississippi, the unit’s home station. The Battalion’s numerical designation in Roman numerals) is suggested by the blue “C” for 100, the V-shape and vertical centerline for six.
The distinctive unit insignia was approved on 28 July 1971. It was rescinded on 16 August 1976.Note: A coat of arms was not approved for this Battalion.