St. Isaac's Cathedral in Saint-Petersburg is the largest cathedral in the city and was the largest church in Russia when it was built (101.5 meters high). It is dedicated to Saint Isaac of Dalmatia, a patron saint of Peter the Great.
The cathedral took 40 years to construct, under direction of French-born architect Auguste de Montferrand, from 1818 to 1858. Both exterior and interior of this magnificent cathedral are worth admiration. Columns, pilasters, floor, and statue of Montferrand are composed of multicolored granites and marbles gathered from all parts of Russia. The iconostasis is framed by eight columns of semiprecious stone: six of malachite and two smaller ones of lapis lazuli. It was the epoch of flourishing of the Ural malachite which was widely used as basic material in interiors. Fifteen tons of this stone, extracted from the mine "Mednorudniansky" in Nizhny Tagil, were used to create these six columns.
The columns tiled with malachite are rare and expensive beyond doubt; moreover in iconostasis of Saint Isaac's Cathedral their height reaches 9.51 meters (31.20”) with the bottom diameter of 1 meter (3.28”). This fact alone makes them really unique in world architecture practice. Malachite columns adorning the iconostasis astonish every visitor with its clear perfection - their surface seems to be made of one piece of malachite - that is the reason for gigantic monolith impression they give.
The Amber Workshop in Tsarskoye Selo was entrusted to restore this unique example of Russian architecture. Stone-carvers of the highest category were involved in the restoration of malachite columns for St. Isaac's Cathedral. Our new mastic and traditional method of «Russian mosaic» were widely used in this project. Today visitors of our city can admire the newly-restored iconostasis and see it in all its splendour.