Stones

Agates are a common variety of brightly coloured quartz. They come in a range of colours depending on the mineral impurities they contain, and can be used in jewelry.

Alexandrite is a beryllium aluminium compound that is a different colour depending on which angle you look at it. The most prized colour combination is a range from green to purple.

Amber is fossilised tree resin. It is a deep orange colour, and sometimes has insects trapped in it.

Amethyst is a violet variety of quartz, with the purple colour coming from trace amounts of iron and aluminium. Amethyst is a popular stone for making jewelry from.

Aquamarine is a clear, pale blue variety of beryl. The blue colour is due to iron impurities.

Aventurine is a type of quartz which has impurities that make it green, translucent, and with a shimmering effect. Some types of aventurine are orange, brown, yellow, blue, or grey but the most common is green. Most of the world's green aventurine is found in India.

Basalt is a common rock made by lava cooling down quickly. Basalt is usually dark grey or black. Depending on how it cools down, basalt can be found in columns like in the picture, in a grid or hexagonal pattern, or even full of bubbles.

Beryl is a colorless mineral made up of beryllium aluminium cyclosilicate. It forms hexagonal crystals that can be very large. When beryl has impurities, it can have a coloured tint or be opaque. Coloured beryl has different names - green beryl is called emerald, pale blue beryl is called aquamarine and pink beryl is called morganite.

Carnelian, also called sard, is a deep red stone often used in jewelry. It is a silicate with large amounts of iron impurities.

Chalk is a soft, white rock that can be used to draw with on rough surfaces. Chalk is usually sold in small coloured sticks, for drawing on blackboards and sidewalks.