Diamond in the Ruff by Anna Markland

Benedict Hawke, son of Dominic and Luisa from Book One, comes of age and feels the need to branch out from his father’s goldsmithing enterprise. He has acquired the skills to operate a successful business on his own, but he lives in challenging times. The Bubonic Plague rages in the parishes outside London, Queen Elizabeth’s popularity is waning as she ages and uncertainty regarding her succession is on everyone’s mind.
Embroiled in this turmoil and confused about his own reluctance to follow in his father’s footsteps as a sexual dominant, he meets Madeline Traverne.
Born in France but raised in India by an abusive father involved in diamond mining, Madeline is the widow of a wealthy Indian maharajah. She and an elderly Dutch diamond merchant form a partnership to sell diamonds to London merchants at a time when the nobility is clamoring to acquire the dazzling gems. The Hawkes intend to take advantage of this trend.
Benedict is intrigued by Madeline, though he should be shocked by her blatant sexual interest in him. She recognizes from her late husband’s teachings that he is the man who can provide what is missing in her life. She has success and wealth but lacks passion and love.