This item is Gillian Anderson's very own childhood violin!
From Yahoo! Chat (March 31, 2001):
Q: Do you yourself play an instrument?
A: You know, I played the violin when I was really little. For about 5 years. And I picked one up a couple of summers ago because my sister plays. And I should have been shot. It was just dreadful. It's not something you pick up after 20 years.
The case is signed by Gillian and comes with a Certificate of Authenticity from the Official Gillian Anderson Website.