(IDEX Online) - A jewelry collection owned by US heiress and philanthropist Mary Anne Sammons Cree is expected to raise over $1.5m for charity.Highlight of the 125-lot auction is a 17.6-carat yellow diamond ring (pictured), with an estimate of $300,000 to $400,000. Cree, who died last July aged 91, was the daughter of the late billionaire Charles Sammons, from Dallas, Texas.In 1938 he founded Sammons Enterprises, which became one of the largest privately-owned companies in the US, with interests in financial services, industrial equipment, real estate investment, and infrastructure businesses.The hybrid online event by Dallas-based Heritage Auctions concludes with a live auction on 29 September. All proceeds will go to for the Communities Foundation of Texas, which manages charitable grants to a range of worthy causes.