Crafted from natural basalt volcanic rock, these whiskey stones deliver sophisticated temperature control without diluting your spirits. Each set includes nine 1-inch stones in rich black-to-gray tones, ready to chill beverages to perfection. Simply freeze and add to drinks already at your desired temperature for optimal results. The included black velvet pouch keeps your stones organized and protected. Elevate your drinking experience with the option to personalize through laser engraving, making these an exceptional gift for the discerning enthusiast.