A stretch bracelet in 8 mm clear quartz beads.
Quartz is the most abundant mineral in the Earth's crust and the one everything else gets compared to. It sits at 7 on the Mohs scale, which is the line above which a stone stops being scratched by ordinary dust and grit, and it is why quartz is the hardest-wearing bracelet material in this range.
Look into the beads rather than at them. Natural quartz carries the record of its own growth: faint internal veils, healed fractures, the odd included crystal. Glass beads are flawless, which is how you tell them apart.
Mineral: Clear quartz, also called rock crystal (SiO₂)
Crystal system: Trigonal
Origin: Not recorded
Hardness: 7 on the Mohs scale; the most durable option in this range
Treatment: None
Approx. inner circumference: 7 cm unstretched
Bead diameter: 8 mm
Approx. weight: 15 g
Stringing: Elastic, stretch fit
Photographed as an example. These are strung in batches from the same material, so yours will be closely similar in colour and pattern but not the exact bracelet pictured.