It's Rutile #4
Like the matched pair of earrings, here is a fine example of rutilated quartz -- with the incredible added bonus of having a cat's eye phenomenon overlaying the rutile. Set in 18k yellow gold with extended bale, making it a gorgeous 'exclamation point' around your neck. There aren't enough !!!!!! to emphasize the beauty of this gem.
SOLD. Ask me about making a similar pendant for you (err, but probably not with a gem such as this). See also the matched pair of earrings, still available: https://www.disegnojewellery.ca/products/its-rutile-3
Contact me about creating your own heirloom.