Yes, that’s a good way to cleanse them. Some crystals are more sensitive to water than others as explained in this Crystal Cleaning Chart.
Set them in a bowl of sea salt for a few minutes. Some are more sensitive but they won’t dissolve immediately. Generally, if you are careful wash them with a soft cloth, your stones will be fine, even if using salt water!
Other ideas: Bathe them in moonlight, or sunlight. Bury them in fresh soil overnight. Let them sit in sea salt, or clear them with smoke from incense.