"No comment," Stone's publicist told UsMagazine.com when asked if the couple had ended their romance.
Stone, 54, and Mica, 27, have been dating for about eight months.
Stone is best known for her work in the film "Basic Instinct." She has been divorced twice and has three sons.
Notable deaths of 2014 [PHOTOS]
Meg Ryan, Kiernan Shipka to star in 'Fan Girl'