stone

A stone is a naturally occurring, solid mass that is made up of one or more minerals. Minerals are the building blocks of rocks, and they come in all shapes and sizes. Some common minerals found in rocks include quartz, feldspar, and mica.

Stones can be found all over the world, and they come in a variety of colours and textures. Some stones are very hard, while others are soft. Some stones are used to make jewellery, while others are used to build houses.

Here are some examples of stones:

• Quartz: A clear or white mineral that is the most abundant mineral in the Earth's crust.
• Feldspar: A group of minerals that make up about 60% of the Earth's crust.
• Mica: A group of minerals that are shiny and flaky.
• Sandstone: A rock made up of sand grains that have been cemented together.
• Limestone: A rock made up of the mineral calcite.

The castle was built of stone.