The Jurassic Mineral Rock is a year round mineral supplement designed to support bigger deer all. It's a 15 lb rock packed with prehistoric minerals to support size, strength and health. Jurassic Rock allows you to create and maintain mineral sites with the best all natural wildlife supplement on the market today. As a year round mineral supplement produced in nature, it is packed with prehistoric minerals to support size, strength and health. Our all natural mineral rock is packed with all the minerals that deer love and need including aluminum, boron, calcium, chromium, cobalt, copper, Iodine, iron, lithium, magnesium, manganese, phosphorous, potassium, selenium, sodium, sulfur and zinc.