Russian Empire. Badge, marking the graduation from Nikolaevsky (Nicholas's) School of Engineers in St Petersburg. Approved on 1.04.1910. Gold Maltese cross covered with white enamel. On the centre of the badge is superimposed a regular hexagon representing in plan a bastion fortress (decreased breastplate of the school). On the hexagon there is laid the gold monogram of Nicholas I under a gold Imperial crown. The inner surface of the hexagon is covered with red enamel and its edging (rampart) is covered with black enamel. The sloping walls of the rampart are covered with alternating stripes of grey and red enamel.
The school, founded in 1804, trained officers for service in sapper, railway, pontoon battalions, as well as mine, telegraph and fortress companies.
The sign is prefabricated, three-tiered. Bronze, hot enamel. Chipped white enamel. Size 40.6*40.6 mm.