3 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>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>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>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>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>Porphyroblast</h2> Subject The topic of the resource <p>A porphyroblast is the metamorphic equivalent of a phenocryst. Do not confuse them! It is a large crystal set into a finer-grained fabric, in a metamorphic rock.</p> Description An account of the resource <div> <div class="element-set"> <div class="element"> <div class="element-text"> <p><em>Compare with<span> </span><a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/236">phenocryst</a>.</em></p> </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>Porphyritic</h2> Subject The topic of the resource <div> <div class="element-set"> <div class="element"> <div class="element-text"> <p>An igneous rock containing phenocrysts in a fine-grained groundmass is said to have a porphyritic texture.</p> </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>Porosity</h2> Subject The topic of the resource <p>The proportion of the material occupied by space, measured in volume percent. A porous material contains fluid-filled spaces, or pores, while a non-porous material does not. NB, make sure you understand the difference between porosity and permeability.</p> Description An account of the resource <div> <div class="element-set"> <div class="element"> <div class="element-text"> <p><em>Compare with<span> </span><a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/234">permeability</a>.</em></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>Polycrystalline</h2> Subject The topic of the resource <p>A crystalline sample of a single mineral, containing many crystals. Quartzite, for example, is polycrystalline quartz.</p> Description An account of the resource <em>Have a look at the <strong>quartzites (<a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/39">L520</a>, <a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/40">L521</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>Poikilitic</h2> Subject The topic of the resource An igneous texture in which a small number of large grains enclose many smaller grains of another phase. Description An account of the resource <em>Have a look at the <strong>gabbro (<a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/10">L141</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>Plutonic</h2> Subject The topic of the resource Plutonic rocks and textures are those associated with deep magmatic intrusions, where cooling is slow. Crystals are thus able to grow very large, producing coarse-grained textures. This term is restricted to large igneous bodies more than hundreds of metres in diameter.