I have a BTT Curved Soprano in ? Raw brass or possibly Gold can't tell (SN 93XXX). I have yet to see another in this color. Do you think its gold? What were the finishes offered?
You would know if it was gold as they do stay shiny. Also look for a worn spot like around the thumbhook etc. If its gold-plated silver would shine thru as they are g/plated over s/plate.
Dave