Solid Marble & Brass Table by John Widdicomb

This table belonged to my Grandfather, who has since given it to me. 

It is a solid marble and brass pedestal table by John Widdicomb. The table is in great condition with no major flaws, defects, or blemishes. The marble is fantastic and the brass inlay has an aged patina. The burl wood base is free of dents, dings, and scratches.From what my own research has gathered, which isn't much, these tables are hard to find. I am interested in selling it and want to know its rough value, and where I should look for a potential buyer.