C.G. CONN Wonder Improved Elkhart model - Silver/Gold Back to model

Here's a very early Conn soprano that dates to the late 1880's to early 1890's. It has no serial number stamp which may imply that it was a prototype. Its also stamped "Elkhart" which implies it was not made in the Worcester factory. I've searched this horn exhustively and can't find a serial number anywhere. It is high pitch.