Brass Music Instrument Trumpet 9k Gold Pendant Charm Vintage c1970.
The gold mark can be found to the bale ring, this mark reads '.375'. There is a tiny indent to the edge of the bell end, this is a product of the manufacture as it is on the seam, it is tiny & does not distract see the pictures.
Size including bale 2.7 x 0.8 x 0.8 cm or 1.0 x 0.3 x 0.3 inches.
Weight 0.9 grams or 0.56 penny weight.