Calling all rock hounds! As a special tie in activity to the exhibit Expedition:  A Natural History Adventure Around the World, each fourth Saturday, BAMA members can take an adventure to Diamond Hill Mine and dig for amethysts. Charge per person is usually $20 to dig, but with a BAMA membership card, visitors will receive a $5 discount each. Check out all that Diamond Hill Mine has to offer at https://diamondhillmine.com/. Dates for special discounts for BAMA members are  Jan.…