9 10 264 Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Description An account of the resource This glossary describes a number of geological terms with which the 1A students should become familiar.<span> It is by no means an exhaustive list, but is aimed to help you understand the material within the first year course.</span> Title A name given to the resource Glossary Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource <h2>Euhedral</h2> Subject The topic of the resource <span>A crystal displaying its characteristic crystal form is called euhedral.</span> Description An account of the resource <em>See: porphyritic andesite (<a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/9">L130</a>)</em> Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Description An account of the resource This glossary describes a number of geological terms with which the 1A students should become familiar.<span> It is by no means an exhaustive list, but is aimed to help you understand the material within the first year course.</span> Title A name given to the resource Glossary Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource <h2>Equant</h2> Subject The topic of the resource <span>A crystal which is of roughly equal size in all directions is described as equant. Although this description implies that equant crystals tend towards a spherical form, the term describes both rounded and angular crystals.</span> Description An account of the resource <em>See: ultramafic cumulate (<a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/14">L171</a>)</em> Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Description An account of the resource This glossary describes a number of geological terms with which the 1A students should become familiar.<span> It is by no means an exhaustive list, but is aimed to help you understand the material within the first year course.</span> Title A name given to the resource Glossary Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource <h2>Eolian</h2> Description An account of the resource <em>See<span> </span><a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/167">aeolian</a>.</em> Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Description An account of the resource This glossary describes a number of geological terms with which the 1A students should become familiar.<span> It is by no means an exhaustive list, but is aimed to help you understand the material within the first year course.</span> Title A name given to the resource Glossary Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource <h2>Dull [lustre]</h2> Subject The topic of the resource <span>Minerals displaying little or no lustre are described as dull. The surfaces of these minerals comprise coarse granulations, which scatter light in all directions. Clay minerals, for example, have dull lustre.</span> Description An account of the resource <em>See: <a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/166">adamantine</a></em> Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Description An account of the resource This glossary describes a number of geological terms with which the 1A students should become familiar.<span> It is by no means an exhaustive list, but is aimed to help you understand the material within the first year course.</span> Title A name given to the resource Glossary Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource <h2>Crystal lattice</h2> Subject The topic of the resource <span>An ordered arrangement of atoms within a solid. This typically exhibits long range order in the form of a repeating motif (unit cell) on each lattice point, to build up the whole structure.</span> Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Description An account of the resource This glossary describes a number of geological terms with which the 1A students should become familiar.<span> It is by no means an exhaustive list, but is aimed to help you understand the material within the first year course.</span> Title A name given to the resource Glossary Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource <h2>Cryptocrystalline</h2> Subject The topic of the resource <span>Rocks with a crystalline structure in which the individual crystals are so small that they cannot be identified using standard optical microscopy are described as cryptocrystalline.</span> Description An account of the resource <em>Compare with<span> </span><a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/227">microcrystalline</a>.</em> Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Description An account of the resource This glossary describes a number of geological terms with which the 1A students should become familiar.<span> It is by no means an exhaustive list, but is aimed to help you understand the material within the first year course.</span> Title A name given to the resource Glossary Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource <h2>Cross-hatched twinning</h2> Subject The topic of the resource <span>Where one set of parallel twin planes intersects another at 90°, twinning is produced in a cross-hatched or tartan pattern. This is a diagnostic characteristic of microcline (an alkali feldspar), and is occasionally referred to as microcline twinning.</span> Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Description An account of the resource This glossary describes a number of geological terms with which the 1A students should become familiar.<span> It is by no means an exhaustive list, but is aimed to help you understand the material within the first year course.</span> Title A name given to the resource Glossary Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource <h2>Conchoidal fracture</h2> Subject The topic of the resource <span>When a brittle material lacking cleavage (plane of weakness) fractures, it breaks into curved fragments. This is conchoidal fracture. Flint, quartz and glass display conchoidal fracture.</span> Description An account of the resource <em>Have a look at the<strong> rhyolite glass (<a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/7">L113</a>)</strong>, the <strong>flint nodule (<a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/35">L370</a>)</strong>, and <strong>quartz (<a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/57">M411</a>)</strong> in the 1A Reference Series.</em> Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Description An account of the resource This glossary describes a number of geological terms with which the 1A students should become familiar.<span> It is by no means an exhaustive list, but is aimed to help you understand the material within the first year course.</span> Title A name given to the resource Glossary Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource <h2>Colour index</h2> Subject The topic of the resource <div> <div class="element-set"> <div class="element"> <div class="element-text"> <p>Rocks can be classified according to their colour index (CI). This describes the proportion of ferromagnesian minerals, such as olivine, pyroxenes, amphiboles and biotite mica, they contain. Colour index is measured in volume percent. The terms used to describe the varying proportions of ferromagnesian minerals are:</p> <ul><li><a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/209">hypermelanic</a>: &gt;90 vol% dark (mafic) minerals</li> <li><a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/222">melanocratic</a>: &gt;60 vol% dark (mafic) minerals</li> <li><a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/223">mesocratic</a>: 30-60 vol% dark (mafic) minerals</li> <li><a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/218">leucocratic</a>: &lt;30 vol% dark (mafic) minerals</li> </ul></div> </div> </div> </div> Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Description An account of the resource This glossary describes a number of geological terms with which the 1A students should become familiar.<span> It is by no means an exhaustive list, but is aimed to help you understand the material within the first year course.</span> Title A name given to the resource Glossary Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource <h2>Cleavage</h2> Subject The topic of the resource <div> <div class="element-set"> <div class="element"> <div class="element-text"> <p class="NoSpacing">Many minerals display very fine, parallel, straight lines called cleavage. Cleavages are the manifestation of planes of weakness within the crystal structure of the mineral. A single crystal may display cleavage in more than one orientation. For example, amphiboles have cleavages which intersect at ~56°, whereas pyroxenes have cleavages which intersect at 90°. </p> </div> </div> </div> </div> <div> <div class="element"> <div class="element-text"></div> <div class="collection"></div> </div> </div>