Antique 38.7mm Agassiz 21 Jewel. Case Size: 38.7 mm. Must have 5 or more positive reviews. GRAY AND SONS JEWELERS is a full service retail store located across from the world famous BAL HARBOUR SHOPS in Miami Beach, Florida.GRAY AND SONS is one of the nation's largest resources for large certified GIA diamonds. Since 1980, we have earned our reputation as a highly regarded and trustworthy jewelry retailer by constantly offering superior quality for new, pre-owned watches and for new & estate jewelry at great prices.