25 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>Prismatic</h2> Subject The topic of the resource <span>An elongate “pencil-like” crystal habit. Prismatic crystals are wider than acicular crystals.</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>Relief</h2> Subject The topic of the resource <p>When viewed under plane polarised light, some mineral grains are more clearly defined than others. They have heavier, darker edges. These minerals have higher relief.</p> <p>Relief is determined by the difference in the refractive indices of the grain and mounting medium. The mounting medium typically has a refractive index (R.I., n_i) of ~1.54. A mineral with a low refractive index, such as quartz (R.I., n_i ~1.5) has low relief because it has a refractive index very similar to that of the mounting medium. A mineral with a high refractive index, such as garnet (R.I., n_i ~1.7) has high relief because it has a refractive index much higher than that of the mounting medium.</p> 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>Replacement</h2> Subject The topic of the resource An igneous texture in which a mineral grain is resorbed and a later crystallising phase grows in its place. 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>Resinous [lustre]</h2> Subject The topic of the resource <div> <div class="element-set"> <div class="element"> <div class="element-text"> <p>Minerals displaying the lustre of resin or of smooth-surfaced plastic are described as resinous. Amber, for example, has resinous lustre.</p> </div> </div> </div> </div> <div> <div class="element"> <div class="element-text"></div> <div class="collection"></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>Rhombohedral cleavage</h2> Subject The topic of the resource <p>Three intersecting cleavage planes. A mineral with rhombohedral cleavage will break up along its cleavage planes into perfect rhombohedra. Calcite, for example, has rhombohedral cleavage.</p> Description An account of the resource <em>Have a look at <strong><a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/64">calcite</a> (M540, M541, M542)</strong> in the 1A Reference Collection.</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>Schistosity</h2> Subject The topic of the resource Schistosity is a type of foliation (planar fabric) found within metamorphosed rocks. It is produced under moderate metamorphic conditions by the alignment and significant recrystallisation of mineral grains. Recrystallised grains are large enough to be seen with the naked eye. 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>Simple twinning</h2> Subject The topic of the resource A single twin plane, producing two twins, within one mineral grain is called a simple twin. The clinopyroxene augite can display simple twinning. Simple twins are occasionally referred to as <a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/179">Carlsbad twins</a>. 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>Solid solution</h2> Subject The topic of the resource Minerals such as quartz have a discrete composition and thus one chemical formula (in this case SiO₂). Other minerals can have a range of compositions between two or three end-member chemical formulae. Olivine, for example, has an end-member composition called forsterite (FeSiO₄). By gradually replacing Fe atoms with Mg atoms, a continuous range of compositions can be produced ending at the Mg end-member, fayallite (MgSiO₄). The range of compositions is called a solid solution. 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>Specific gravity, D</h2> Subject The topic of the resource This is a measure of density. It is the ratio of the density of the substance being described (e.g. a mineral) to the density of water. Olivine has a specific density, D = 3.222, which means that olivine is 3.222 times more dense than water. Since water has a density of 1 g cm^-3, olivine has a density of 3.22 g cm^-3. 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>Splendent [lustre]</h2> Description An account of the resource <em>See <strong><a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/224">metallic</a></strong>.</em>