The egg unscrews to reveal the inside carvings to hold needles and thread, and probably a thimble. Thread, needles and thimble not included.

See photos.... This is a real gem for someone who collects old sewing etuis , wooden eggs. 

Can't confirm if Scottish Mauchline ware as any markings are no longer present. 

Length:-    3 inches / 75mm,   Diameter 1 7/8 inches / 47mm