It is what the Waterbury Button Company calls a "Career Uniform" button... meaning buttons worn on the uniform of trainmen, hotel staff, cruise ship lines, etc. Based on the lettering style, I believe yours is from the late-1800s into the early 1900s. Also based on the lettering "logo" style, I believe your "CT Co." button is from a Streetcar/Trolley Conductor's uniform. Here's a very similar one, from the Union Traction Company, which was a Trolley/Streetcar line. Yours is probably from the C____ Traction Company.