Provided it is dried immediately, turquoise jewelry can be washed with warm sudsy water. It should be handled and stored carefully to avoid scratching and should be kept away from high heat and chemicals.
Garnets can also be cleaned with warm soapy water and a soft brush but they should be rinsed well. Exposure to harsh temperatures, chemicals and sharp blows should be avoided.
Avoid vigorous polishing of your vermeil jewelry so as not to destroy the gold coating, and never expose it to moisture. Keeping it in a zip-lock bag will prevent moisture and humidity from attacking it.