I have a violin that looks to be 18th century Italian or German, with pre-Guarneri or "Cremona" arching, perfectly matched top and back, not as high as the really high Baroque arching. The ground for an oil varnish is a slightly golden amber. The neck has space for the nut that includes a slot in the neck, thus requiring a mitred nut design. The violin has a lot of bad repairs on the inside, but the outside is has had very little done. Could this nut design be original and if so, does it indicate any country, school, or maker?