These are adjustable, so they will fit a variety of of sizes.  It’s a fabulous snake design with aventurine set in there. 
Aventurine 
Keywords: Abundance, Luck, Positivity , Healing 
Element: Earth 
Planet:  Mercury 
Aventurine is a style of quartz. It is most commonly green but also comes in shades of blue, red, orange, grey and brown. It has a platy minerals in the quartz that give it a shimmering quality known as aventurescence. Aventurine belongs to the mineral class of Chalcedony. Aventurine's meaning is prosperity and confidence. Aventurine meaning comes from the Italian word Aventura which means chance, a hint at the great fortune this stone can bestow upon you. It’s a form of quartz that often comes to us in a dark green color flecked with suggestions of gold.
Perhaps it was this golden quality that made it such a sought-after gem, but for centuries Aventurine was called The Stone of the Amazons. It was said to be the stone that guarded the shields of Amazon Warrior Queens, tapping into divine femininity, fierce power, and protection.  
It’s a comforter, a harmonizer, and a super handy stone to have stashed on the self for all those who want to bring a little more luck into their world. Whether you need a little flush of added wealth, an extra abundance of love and friendship, or just a bit more growth, Aventurine wants one thing – for you to succeed in all your amazing endeavours, no matter how big or small they may be. 
Green Aventurine is the most popular version of this wealthy and wonderful stone. For those who are keen to attract a little more of Lady Luck’s energy into their world, Green Aventurine is the stone to turn to. Along with being a talisman of good fortune, this stone is also ready to soothe the soul, regulate your energy, and keep your heart open and ready to receive. It also helps soothe anxiety and stress. Aventurine is your go-to good luck crystal. It is a powerfully positive stone that just seems to attract abundance in many waves. Whether it's being a go-getter when it comes to your career, finding success in friendship and the bloom of beautiful love, tapping into a lost creative spirit, or simply finding abundance within your own soul, the soothing energy of Aventurine is a dream.