"Where's my tigerseye? No, I need my tigerseye, it means good luck. No, no, I gotta get my tigerseye!" --Gillian, Practical Magic
As I understand it at one time Gillian's necklace was actually manufactured and sold. Despite this, I have never been able to find an accurate representation of Gillian's Tigerseye necklace.
I once spent an entire afternoon replaying the few scenes the necklace is visible, pausing and staring at the necklace in hopes of divining what exactly it looks like. This is what I've determined so far:
The tigerseye is carved into either a sphere or a rounded point. It is situated below a single-terminated clear quartz point. The crystal is pointed upwards towards the wearer. I cannot determine whether the metal was composed of gold or silver, lighting is too tinted to determine pure color. Considering Gillian's personality my bet is on the gold (more firey).
There is metal trailing across the surface of the crystal in some sort of pattern...I've never been able to determine what exactly it is. Instinct says something asian, either a tiger or chinese dragon. It could also be a vine pattern.
Magickal properties of this necklace: Traditionally with this stone's color of brown/yellow indicates that it is a grounding earthy stone as well as having some draw in the the mental sphere. The colorplay suggests that it would do well for divination as well. I've always thought of tigerseye as a very sensual stone, likely due to the tiger associations. Some other added magical properties of this stone are courage, energy, and luck. Tiger's eye is ruled by the Sun. Holding it in your hands can promote courage and confidence whenever you need it.
I find the fact that there are no images on the internet of this necklace remarkable, by the way. You'd think with such a popular movie that there would at least be an image...there are plenty of images of Jimmy's ring after all! Grr...