Platinum Squared Mariner Chain. Mariner link is a classic, the squared design gives this Platinum chain a modern kick. Chain measures 5.6mm (also custom made in 5mm, 6.6mm) and available in any custom length. Quality Platinum chain is secured with a swivel lobster style clasp. Price shown is for the suggested 8 1/2 inch bracelet weighing approx. 39.08grams. Email for additional pricing. Suggested lengths listed below.