Measurements: small: 15.5 inches  large: 17.5 inches xl: 24 inches. Coin: dainty generic coins with no affiliation to money, .5 of an inch. Closure: lobster clasp - a great pair to our aura link and potentially could be sold in a set as it is out best selling set. " Care instruction: We always recommend for anything that is not solid gold to avoid liquids, perfumes and lotions. Don’t worry our beautiful pieces will hold up to the elements of daily life,  but remember they are not solid gold!  We want our products to work for you, not the other way around! To maintain that it is important to keep your jewelry clean! Without doing so, your pieces can become temporarily darkened due to buildup. To clean use a soft cloth or microfiber towel to wipe away dirt and oil buildup after use, and remember keep your jewelry dry! We always want you to sparkle baby, but without proper care there is always a higher risk of fading or buildup!"