(IDEX Online) - India's prime minister Narendra Modi presented US First Lady Jill Biden with a 7.5-carat lab grown diamond on a visit to the White House.The gem is "a beacon of responsible luxury that symbolises India's 75 years of freedom and sustainable international relations," said the Prime Minister's Office.It expanded on the diamond's eco-friendly credentials, saying it was made using solar and wind power.The gem was graded by the IGI lab, but India's Ministry of External Affairs (MEA) did not disclose further details.The gifts exchanged by head of states are carefully considered and highly symbolic. During his three-day visit, Prime minister Modi also presented President Joe Biden with a sandalwood box meant to "symbolise" the rituals mentioned in the ancient Indian text Krishna Yajurveda's Vaikhanas Grihya Sutram, and a first-edition print of The Ten Principal Upanishads.Pic of the diamond, courtesy Ministry of External Affairs (MEA)