_ The Hon Teresa Mary (Tessa) Tennant (nee Cormack), who has died aged 59, was the chatelaine of Glen House, the Scottish seat of the eccentric and ill-starred Tennant dynasty into which she married.
Bohemian socialite Mrs Tennant was a pioneering advocate of 'green investment', and made her mark in the city of London as co-founder in 1988 of the Merlin (later Jupiter) Ecology Fund.
She was born Teresa Mary Cormack, 29 May, 1959, daughter of John McRae Cormack, AFC, by his wife the former Hon Gwendoline Rita Jean Davies (b 1929), scion of the Barons Davies (cr 1932), and married 5 January, 1983, the Hon Henry Lovell Tennant (1960-90), second son of the 3rd Baron Glenconner (1926-2010), by his wife the former Lady Anne Coke, LVO, scion of the Earls of Leicester.
Her husband, in the late 1980s, caused a scandal by announcing he was gay, and he left his wife and infant son, but died of AIDS in 1990. She married secondly, in 2007, William Staempfli.
Mrs Tennant is survived by an only son, Euan Lovell Tennant, who was born in 1983, and his heir presumptive to his cousin, the 4th Baron Glenconner.