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<p><img src="../en/images/materials_title.gif" width="99" height="25" alt="Materials">
<a href="MethodsFrameEn.html"><img name="methods" border="0" src="images/methodsOff.gif" width="65" height="19" alt="methods" title="Learn more about methods used to create ceramic art"></a><img name="materials" border="0" src="images/materialsOff.gif" width="60" height="19" alt="materials" title="Discover some of the materials used in ceramic art"><a href="FiringFrameEn.html"><img name="firing" border="0" src="images/firingOff.gif" width="39" height="19" alt="firing" title="Understand more about the process that turns clay into ceramic"></a><a href="DecorationsFrameEn.html"><img name="decorations" border="0" src="images/decorationsOff.gif" width="83" height="19" alt="decorations" title="Explore techniques used to add details to a piece"></a>
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<p><span class="title">Introduction to Clay</span><br>
<span class="bodytext">Clay is produced in the decomposition of granite and
igneous rock where the alkalis have washed out leaving behind quartz, mica,
and clay. Primary clay is found where it was formed, it is not weathered and
therefore - having fewer impurities - is whiter. Secondary clay has been moved
by geological forces, by glacial action, by rock folding, by water, or by wind
so the clay is finer in particle size. It has also picked up many impurities
that alter the rate of shrinkage, the drying time, the firing temperature, and
the colour. The most common impurity is iron oxide - we know it as rust - that
gives most earthenware its red colour.<br>
</span><span class="menutia">Introduction to Clay Video <a href="video/materials/IntroClayLowEn.html" title="Johnathan Smith introduces the basics of clay">small</a>
(2.7 Mb) <a href="video/materials/IntroClayHighEn.html" title="Johnathan Smith introduces the basics of clay">large</a>
(3.9 Mb) | Clay Types Video <a href="video/materials/ClaytypesLowEn.html" title="Robin Hopper discussing the differing types of clay">small</a>
(3.0 Mb) <a href="video/materials/ClaytypesHighEn.html" title="Robin Hopper discussing the differing types of clay">large</a>
(5.4 Mb) | Clay Progression Video <a href="video/materials/ClayprogressLowEn.html" title="Robin Hopper discusses how raw clay is formed">small</a>
(3.0 Mb) <a href="video/materials/ClayprogressHighEn.html" title="Robin Hopper discusses how raw clay is formed">large</a>
(7.8</span><span class="menutia"> Mb)</span></p>
<p><span class="title">Earthenware</span><span class="bodytext"><br>
</span><span class="bodytext">Earthenware makes up the majority of clay work.
It is also known as raku, slipware, terra cotta, lusterware, maiolica, faience,
or delftware. Earthenware is a secondary clay and is normally red but also comes
in the colour of buff, sand, and white. It is normally fired to 1150 degrees
celsius. It is not fired to vitrification which is the point where clay melts.
It is slightly porous and generally glazed.</span><br>
<span class="menutia">Earthenware Video <a href="video/materials/EarthenwareLowEn.html" title="A description of the properties of earthenware clay">small</a>
(2.0 Mb) <a href="video/materials/EarthenwareHighEn.html" title="A description of the properties of earthenware clay">large</a>
(3.9 Mb) | <a href="examples/JasminJoggingEnForetEn.html" title="View an example of earthenware by Edouard Jasmin">artwork
example</a></span></p>
<p><span class="title">Stoneware</span><span class="bodytext"><br>
Stoneware is a secondary clay which has been fired to a temperature between
1150 and 1300 degrees celsius. It is hard, durable, almost impervious to thermal
shock and is usually, buff, grey or red-brown in colour.</span><br>
<span class="menutia">Stoneware Video <a href="video/materials/StonewareLowEn.html" title="A description of stoneware clay">small</a>
(1.3 Mb) <a href="video/materials/StonewareHighEn.html" title="A description of stoneware clay">large</a>
(6.3 Mb) | <a href="examples/DoucetSaitoUntitledEn.html" title="View an example of stoneware by Louise Doucet and Satoshi Saito">artwork
example</a></span></p>
<p><span class="title">Raku</span><span class="bodytext"><br>
Raku clay is technically an earthenware that has been modified with the addition
of grog. Grog is a ground fired bisqueware. In other words, clay that has already
been through the firing. Depending on the size of the grog it can add texture
to the clay but more importantly it also reduces shrinkage and helps prevent
thermal shock that is part of the raku process. Raku is normally fired from
900 to 1000 degrees.</span><br>
<span class="menutia">Raku Video <a href="video/materials/RakuLowEn.html" title="The properties of raku clay">small</a>
(2.2 Mb) <a href="video/materials/RakuHighEn.html" title="The properties of raku clay">large</a>
(4.1 Mb) | <a href="examples/OliveMufflerTeapotEn.html" title="View an example of raku by Agnes Olive">artwork
example</a></span></p>
<p><span class="title">Porcelain</span><span class="bodytext"><br>
Porcelain is a primary clay generally composed of kaolin or aluminasilicate.
This produces a product that is known for its whiteness, hardness, durability
and translucency when thin enough. A distinctive ring is produced when it is
struck. Porcelain is fired to the point of vitrification or melting at a temperature
between 1250 degrees and 1400 degrees celsius.</span><br>
<span class="menutia">Porcelain Video <a href="video/materials/MnMPorcLow.html" title="Learn more about porcelain clay">Low</a>
(2.3 Mb) - <a href="video/materials/MnMPorcHigh.html" title="Learn more about porcelain clay">High</a>
(5.6 Mb) | <a href="examples/NasrBasketEn.html" title="View an example of porcelain by Diane Nasr">artwork
example</a></span></p>
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