This is such a lovely ring steeped in history. Dating from the late Victorian era and set with a blue zircon. The Zircon is such a sparkly stone due to its high birefringence (double refraction) and even with the wear this stone has on the facet edges it is still beautiful. This is reflected in the price.
 
UK ring size O - O 1/2, setting 9x9x6mm, band 2mm
2.57g
The metal is testing as 9ct yellow gold
Blue Zircon 7mm, estimated weight 1.67cts
 
Good condition for its age, signs of wear to the metal and to the stones facet edges
 
Zircon is a natural gemstone (not to be confused with cubic zirconia) known for its high brilliance and sparkle, and can be found in various colours including blue, red, brown, and yellow, though most blue and colourless zircons are heat-treated from brown origins. It is the oldest mineral on Earth next to diamond. It is  6-7 on the Mohs scale of hardness and on the brittle side, we advised to remove zircon jewellery for any rough activities, and it should never be cleaned with ultrasonic or steam. 
 
The gem is believed to help keep people grounded and to promote intuitive and psychic abilities, so it is frequently used during meditation. Many believe that zircon can help a person’s dreams become reality, and that connecting with the stone physically and mentally can enhance visions and provide guidance and purpose.