As indicated by the caption, this image Clarence Mackay's mother's famed Mackay, Tiffany & Co. silver candelabra.
The caption accompanying this photograph reads as follows:
After 1920, when Clarence Mackay's mother moved to Harbor Hill to act as his hostess, she brought with her the famed Mackay, Tiffany & Co. silver. Her husband had sent a half-ton of ore from his own mine for it. Awarded a prize when exhibited at the Paris Exposition Universelle in 1878, the dinner and desert service for 24, comprised, 250 pieces. It included as well hollowware and centerpieces. Flower-encrusted with thistles, shamrocks, and blossoms native to American, the unique creation took two years and 200 craftsmen to complete.
See Harbor Hill, Clarence Hungerford Mackay's Mansion.