Map Keystone Antiques 110 E. Michigan Ave., Marshall, MI 49068 Add To Trip WebsiteEmailPhone: (269) 789-1355 Description General and architectural antiques. Our shop contains three floors with an endless variety of antiques. Open 1:00 pm - 5:00 pm. Wed., Thur., Fri. and Sun. 10:00 am - 5:00 pm Sat. and by appointment. Closed Monday and Tuesday. Videos TripAdvisor® Traveler Reviews More To Explore Categories: Antiques & Flea Markets Shopping City: Marshall Region: Southwest Although the MEDC uses reasonable efforts to maintain the accuracy of the website content, it is not represented to be error free. Read legal information.