Jonathan Phillips ; http://www.flickr.com/photos/paperbydesign/359036434/
You should only use a special type of brick, called firebrick, fire brick or a refractory brick, to make a fireplace. Normal bricks cannot stand up to the continued high heat inside a fireplace and will crack.
In 1817 William Harry was the first to apply silica tiles to a ceramic kiln to prolong its life. However, William Weston Young was the one who through his own experimentation of different silica clays first created a long-lasting brick that is basically heat-proof. In 1822 Young and a group of investors first began making and producing firebricks.
In order to create firebricks, a special mixture called fire clay must be created from a mixture of silica, aluminium oxide and other materials that stand up well to high temperatures. The clay is then baked in a kiln until vitrified.
The refractory properties of firebricks makes them very popular for a variety of applications. Not only are firebricks useful in fireplaces for people's home, but also for industrial furnaces, steel refineries and even as insulating tiles for the space shuttle.
Firebricks are rectangles usually measuring 9 x 4.5 x 2.5 in. This is the standard size, but it may vary as they are adapted for specific applications.
Do not attempt to build a fireplace out of normal bricks. The bricks could crack under the heat and it could endanger the integrity of the whole fireplace and collapse.
- Jonathan Phillips ; http://www.flickr.com/photos/paperbydesign/359036434/