Crack the mysteries of rocks & dig out their sparkling secrets in this visually stunning pocket guide, packed with amazing photos & dramatic facts. From the hardest stone to the most beautiful jewels, find out why sapphires are blue, what marble is made from & how granite gets its legendary toughness. Find out where & how rocks & minerals form, & what creates their hardness, colour & lustre. You’ll find the best topics, the best facts & the most breathtaking photos in this wow-factor series: a fresh look at it all!