Simple text and photographs describe what opals look like, where they are found, how they are used, what makes them valuable, and other related topics.
Simple text and photographs describe what rubies look like, where they are found, how they are used, what makes them valuable, and other related topics.
Simple text and photographs describe what emeralds look like, where they are found, how they are used, what makes them valuable, and other related topics.
Simple text and photographs describe what sapphires look like, where they are found, how they are used, what makes them valuable, and other related topics.
Simple text and photographs describe what diamonds look like, where they are found, how they are used, what makes them valuable, and other related topics.