good day this is very old flute made in 1957 so 65 years ago and is in the case and suprisely the plain is not tarnish at all I really do not know way maybe somebody that knows this instrument can help me is not silver I lock everywhere for it has 233 number in one side and between the key is one more number36233 apparently this mean that is been made 1957 thanks you please let me know any info that can help