15 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>Bladed</h2> <div class="element-set"> <div class="element"></div> <div class="element"></div> <div class="element"> <div class="element-text"></div> </div> </div> Subject The topic of the resource <span>Crystals with a flattened, elongate habit, resembling blades of grass are described as bladed. Bladed crystals are more elongate than platy crystals, and thinner than tabular crystals.</span> https://wserv3.esc.cam.ac.uk/p1acollections/files/original/607dd801b6adf46497c9418c3fd72394.png a16b40b3163926bfad9f26045b1d2f4f https://wserv3.esc.cam.ac.uk/p1acollections/files/original/0e34c9106c2cbdf6715affea864aecb8.png b36238a2f85be777e5e0bed70b9fdc61 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 Fossils Description An account of the resource <p>Welcome to the fossils section of the website. This is designed to help you learn the different characteristics of each major fossil group so that you are able to distinguish between them.</p> <p>First year students, please refer to the specimens housed in the first year teaching laboratory. There is no substitute for handling the specimens themselves; this website is just an accessory to help you along the way.</p> <p>Animals occupy different environments, have different life habits and lived through different periods in geological time. It is good to be aware of these differences in lifestyle and timing, within and between phyla, classes, orders and families.</p> Physical Object An inanimate, three-dimensional object or substance. Note that digital representations of, or surrogates for, these objects should use Moving Image, Still Image, Text or one of the other types. 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>Brachiopod</h2> Description An account of the resource <h2>Taxonomy</h2> <p>Phylum: Brachiopoda</p> <h2>Diagnostic features</h2> <p>Two valves (brachial and pedicle)</p> <p>Bilateral symmetry</p> <p>Growth lines</p> <p>Adductor and ductor muscle scars</p> <p>Pedicle</p> <p>Commissure</p> <p>Gape</p> <p>Teeth and socket (articulates; no teeth or socket in inarticulates)</p> <h2>Stratigraphic range</h2> <p>Cambrian to present</p> <h2>Way of life</h2> <p>Marine</p> <p>Attach to hard substrates using pedicle</p> <p>Filter feeding</p> <p>Sessile</p> <p>Infaunal, epifaunal, reclining</p> <h2>Advanced notes</h2> <p>Apparent decrease in diversity over time</p> <p>Limited to marginal environments in the modern ocean</p> <p>Adductor muscle used to close shell, ductor muscle used to open shell</p> <h2>Specimens</h2> <p><a href="/p1acollections/exhibits/show/brachiopods">Browse brachiopods</a></p> <h2>External links</h2> <p><a href="http://peabody.yale.edu/collections/blog/2011-11-07/brachiopods-versus-bivalves" target="_blank" rel="noreferrer noopener">Yale Peabody Museum of Natural History</a>: differences between bivalves and brachiopods</p> <p><a href="http://paleo.cortland.edu/tutorial/Brachiopods/brachmorph.htm">Cortland Paleo, Brachiopoda</a>: brachiopod morphology and ecology information</p> <p><a href="https://www.digitalatlasofancientlife.org/learn/nature-fossil-record/types-of-fossil-preservation/">Learn about types of preservation</a></p> sessile symmetry https://wserv3.esc.cam.ac.uk/p1acollections/files/original/131f9fed02c94c7ed59fdcc2af090a2a.jpg 643ac9583c58d950875775f7e70d6eb2 https://wserv3.esc.cam.ac.uk/p1acollections/files/original/1601e70da0052a68594dec7a2514dd02.jpg 1cb9f4472a97823a8d51134194c923e3 https://wserv3.esc.cam.ac.uk/p1acollections/files/original/cbeadd5a56f3203f1ba3e826c6a47243.jpg 36e3ea225c5242449ca4f9d8338eeda2 https://wserv3.esc.cam.ac.uk/p1acollections/files/original/90389dcc429c1645fb7b37c3c2614530.jpg 1cd30f0903ab9fe7bf55172c5f95e63f Physical Object An inanimate, three-dimensional object or substance. Note that digital representations of, or surrogates for, these objects should use Moving Image, Still Image, Text or one of the other types. 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>Calcite</h2> Description An account of the resource <div class="element"> <h3>Formula</h3> <div class="element-text"> <p>CaCO₃</p> </div> </div> <div class="element"> <h3>Structure</h3> <div class="element-text"> <p>Non-silicate</p> </div> </div> <div class="element"> <h3>Crystal System</h3> <div class="element-text"> <p><em>Crystal system:</em><span> </span>trigonal (-)</p> </div> </div> <div class="element"> <h3>Physical Properties</h3> <div class="element-text"> <p><em>Colour in hand specimen:</em><span> </span>white<br /><em>Cleavage:</em><span> </span>rhombohedral<br /><em>Hardness:</em><span> </span>3</p> </div> </div> <div class="element"> <h3>Optical Properties</h3> <div class="element-text"> <p class="NoSpacing"><em><span>Colour in plane polarised light:</span></em><span> colourless</span><span> </span><br class="NoSpacing" /><em><span>Pleochroism:</span></em><span> none</span><span> </span><br class="NoSpacing" /><em><span>Relief:</span></em><span> low</span><span> </span><br class="NoSpacing" /><em><span>Birefringence:</span></em><span>0.172-(0.190); &gt;4^th order</span><span> </span><br class="NoSpacing" /><em><span>Extinction:</span></em><span> inclined</span><span> </span><br class="NoSpacing" /><em><span>Twinning:</span></em><span> lamellar, common</span></p> </div> </div> <div class="element"> <h3>Mineral Specimens</h3> <div class="element-text"> <p class="NoSpacing"><strong><span>M540 Calcite with banded hematite</span></strong><span> </span><br class="NoSpacing" /><strong><span>Egremont, Cumberland</span></strong><span> </span><br class="NoSpacing" /><span>Mass of acicular (needle-like) calcite crystals</span><span> </span><br class="NoSpacing" /><span>Colourless with some grey and red impurities</span></p> <p class="NoSpacing"><strong><span>M541 Calcite</span></strong><span> </span><br class="NoSpacing" /><strong><span>Iceland spar</span></strong><span> </span><br class="NoSpacing" /><strong><span>Iskifjördhr</span></strong><strong><span>, Iceland</span></strong><strong></strong><span> </span><br class="NoSpacing" /><span>Single crystal of calcite</span><span> </span><br class="NoSpacing" /><span>Colourless, transparent</span><span> </span><br class="NoSpacing" /><span>Hardness 3</span><span> </span><br class="NoSpacing" /><span>Observe the double refraction </span><br class="NoSpacing" /><span>Rhombohedral cleavage (three cleavages)</span></p> <p class="NoSpacing"><strong><span>M542 Calcite vein material</span></strong><span> </span><br class="NoSpacing" /><strong><span>Minsterley, Shropshire</span></strong><span> </span><br class="NoSpacing" /><span>Rhombohedral cleavage (three cleavages)</span><span> </span><br class="NoSpacing" /><span>Pearly lustre</span><span> </span><br class="NoSpacing" /><span>Hardness 3</span></p> </div> </div> <div class="element"> <h3>Rock Specimens</h3> <div class="element-text"> <p><a href="/p1acollections/exhibits/show/igneous-rocks/l110">L110 Rhyolite, porphyritic (quartz porphyry)</a><span> </span><br /><a href="/p1acollections/exhibits/show/igneous-rocks/l130">L130 Andesite, porphyritic (porphyrite)</a><span> </span><br /><a href="/p1acollections/exhibits/show/igneous-rocks/l161">L161 Basalt, amygdaloidal</a><br /><a href="/exhibits/show/sedimentary-rocks/l325">L325 Sandstone, calcareous cement</a><span> </span><br /><a href="/p1acollections/exhibits/show/sedimentary-rocks/l341">L341 Mudstone, calcareous</a><span> </span><br /><a href="/p1acollections/exhibits/show/sedimentary-rocks/l350">L350 Limestone, argillaceous</a><span> </span><br /><a href="/p1acollections/exhibits/show/sedimentary-rocks/l353">L353 Limestone, oolitic, packstone</a><span> </span><br /><a href="/p1acollections/exhibits/show/sedimentary-rocks/l371">L371 Chert, bedded</a></p> </div> </div> <div class="element"> <h3>Mineral Name</h3> <div class="element-text">calcite carbonate</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>Carlsbad twinning</h2> Subject The topic of the resource <div> <div class="element-set"> <div class="element"> <div class="element-text"> <p></p> </div> </div> </div> </div> <div> <div class="element"> <div class="element-text"></div> <div class="collection"></div> </div> </div> Description An account of the resource <em>See<span> </span><a href="https://wserv3.esc.cam.ac.uk/p1acollections/items/show/252">simple twins</a>.</em> https://wserv3.esc.cam.ac.uk/p1acollections/files/original/696687461afd25ae14285b6fab757bfc.jpg 6283ac65e1ab3970a7982cdbaf1f06d7 Physical Object An inanimate, three-dimensional object or substance. Note that digital representations of, or surrogates for, these objects should use Moving Image, Still Image, Text or one of the other types. 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>Chlorite</h2> Subject The topic of the resource <span>Chlorite is a common high-temperature alteration product of ferromagnesian minerals (such as biotite) in igneous rocks. It is stable in the upper part of the crust and is a major constituent of the metamorphic rocks known as greenschists.</span> Description An account of the resource <div class="element-set"> <div class="element"> <div class="element-text"> <h3 class="NoSpacing">Formula</h3> </div> </div> </div> <div class="element-set"> <div class="element"> <div class="element-text">(Mg,Fe²⁺,Fe³⁺,Mn,Al)₁₂[(Si,Al)₈O₂₀](OH)₁₆</div> </div> <div class="element"> <h3>Structure</h3> <div class="element-text"> <p>Sheet silicate</p> </div> </div> <div class="element"> <h3>Crystal System</h3> <div class="element-text"> <p><em>Crystal system:</em><span> </span>monoclinic (+) (-)</p> </div> </div> <div class="element"> <h3>Physical Properties</h3> <div class="element-text"> <p class="NoSpacing"><em><span>Colour in hand specimen:</span></em><span> green</span><span> </span><br class="NoSpacing" /><em><span>Cleavage:</span></em><span> one, good</span><span> </span><br class="NoSpacing" /><em><span>Hardness:</span></em><span> 2-3</span></p> </div> </div> <div class="element"> <h3>Optical Properties</h3> <div class="element-text"> <p class="NoSpacing"><em>Colour in plane polarised light:</em><span> </span>colourless or green<span> </span><br class="NoSpacing" /><em>Pleochroism:</em><span> </span>weak to moderate<span> </span><br class="NoSpacing" /><em>Relief:</em><span> </span>low<span> </span><br class="NoSpacing" /><em>Birefringence:</em><span> </span>anomalous (blue or brown colours that do not appear in the Michel-Levy chart)<span> </span><br /><em>Extinction:</em><span> </span>straight</p> </div> </div> <div class="element"> <h3>Rock Specimens</h3> <div class="element-text"> <p><a href="/p1acollections/exhibits/show/igneous-rocks/l100">L100 Alkali granite</a><span> </span><br class="NoSpacing" /><a href="/p1acollections/exhibits/show/igneous-rocks/l101">L101 Granite</a><span> </span><br class="NoSpacing" /><a href="/p1acollections/exhibits/show/igneous-rocks/l120">L120 Granodiorite</a><span> </span><br class="NoSpacing" /><a href="/p1acollections/exhibits/show/igneous-rocks/l130">L130 Andesite, porphyritic (porphyrite)</a><span> </span><br class="NoSpacing" /><a href="/p1acollections/exhibits/show/igneous-rocks/l161">L161 Basalt, amygdaloidal</a><span> </span><br /><a href="/p1acollections/exhibits/show/volcaniclastic-rocks/l201">L201 Tuff</a><span> </span><br /><a href="/p1acollections/exhibits/show/metamorphic-rocks/l504">L504 Garnet schist</a></p> </div> </div> <div class="element"> <h3>Mineral Name</h3> <div class="element-text">chlorite</div> </div> </div> alteration metamorphism 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> https://wserv3.esc.cam.ac.uk/p1acollections/files/original/ac4a4b68b6b2ad4fef27b63699c1a3bf.jpg 7f450bfca482d0fe4649c3f6f70d4afa Physical Object An inanimate, three-dimensional object or substance. Note that digital representations of, or surrogates for, these objects should use Moving Image, Still Image, Text or one of the other types. 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>Clinopyroxene (augite)</h2> Description An account of the resource <div class="element"> <h3>Formula</h3> <div class="element-text">(Ca,Mg,Fe²⁺,Fe³⁺,Ti,Al)₂[(Si,Al)₂O₆]</div> </div> <div class="element"> <h3>Structure</h3> <div class="element-text"> <p>Chain silicate</p> </div> </div> <div class="element"> <h3>Crystal System</h3> <div class="element-text"> <p><em>Crystal</em><em><span> </span>system:</em><span> </span>monoclinic (+)</p> </div> </div> <div class="element"> <h3>Physical Properties</h3> <div class="element-text"> <p class="NoSpacing"><em><span>Colour in hand specimen:</span></em><span> black</span><span> </span><br class="NoSpacing" /><em><span>Cleavage:</span></em><span> two at 90°</span><span> </span><br class="NoSpacing" /><em><span>Hardness:</span></em><span> 5.5-6</span></p> </div> </div> <div class="element"> <h3>Optical Properties</h3> <div class="element-text"> <p class="NoSpacing"><em>Colour in plane polarised light:</em><span> </span>colourless, pale brown or pale grey<span> </span><br class="NoSpacing" /><em>Pleochroism:</em><span> </span>variable weak to moderate<span> </span><br class="NoSpacing" /><em>Relief:</em><span> </span>moderate<span> </span><br class="NoSpacing" /><em>Birefringence:</em><span> </span>0.018-0.033; 1^st<span> </span>order pink to 2^nd<span> </span>order orange<span> </span><br class="NoSpacing" /><em>Extinction:</em><span> </span>inclined<span> </span><em><br />Twinning:</em><span> </span>simple, common</p> </div> </div> <div class="element"> <h3>Rock Specimens</h3> <div class="element-text"> <p><a href="/p1acollections/exhibits/show/igneous-rocks/l141">L141 Gabbro</a><span> </span><br /><a href="/p1acollections/exhibits/show/igneous-rocks/l161">L161 Basalt, amygdaloidal</a><span> </span><br /><a href="/p1acollections/exhibits/show/igneous-rocks/l162">L162 Basalt, porphyritic</a><span> </span><br /><a href="/p1acollections/exhibits/show/igneous-rocks/l172">L172 Ultramafic cumulate</a></p> </div> </div> <div class="element"> <h3>Advanced Notes</h3> <div class="element-text"> <p class="NoSpacing"><span>Clinopyroxene contains calcium. It encompasses a range of solid solutions from (Mg,Fe)₂[Si₂O₆] to Ca(Mg,Fe)[Si₂O₆]. The physical and optical properties detailed above refer to augite, a clinopyroxene common in mafic igneous rocks.</span></p> </div> </div> <div class="element"> <h3>Mineral Name</h3> <div class="element-text">clinopyroxene<br />augite</div> </div> mafic ultramafic 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>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/. Title A name given to the resource Fossils Description An account of the resource <p>Welcome to the fossils section of the website. This is designed to help you learn the different characteristics of each major fossil group so that you are able to distinguish between them.</p> <p>First year students, please refer to the specimens housed in the first year teaching laboratory. There is no substitute for handling the specimens themselves; this website is just an accessory to help you along the way.</p> <p>Animals occupy different environments, have different life habits and lived through different periods in geological time. It is good to be aware of these differences in lifestyle and timing, within and between phyla, classes, orders and families.</p> Physical Object An inanimate, three-dimensional object or substance. Note that digital representations of, or surrogates for, these objects should use Moving Image, Still Image, Text or one of the other types. 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>Coral</h2> Description An account of the resource <h2>Taxonomy</h2> <p>Phylum: Cnidaria</p> <p>Class: Anthozoa</p> <h2>Diagnostic features</h2> <p>Radial or biradial symmetry</p> <p>External skeleton</p> <p>Septa</p> <p>Tabulae</p> <h2>Stratigraphic range</h2> <p>Ordovician to present</p> <p>Tabulate, rugose: Ordovician to Permian (extinct at P/T extinction)</p> <p>Scleractinian: Triassic to present</p> <h2>Way of life</h2> <p>Colonial or solitary</p> <p>Filter feeding</p> <p>Reef builders</p> <h2>Advanced notes</h2> <p>Remember, although the most well-known modern corals enjoy a symbiotic relationship with photosynthesising algae (Zooxanthellea) many modern corals do not. When thinking about Palaeozoic corals do not assume that they lived as well known corals do now.</p> <p>Corals built their skeletons out of aragonite (Ordovician to Permian) or calcite (Triassic to recent). They are often preserved as moulds, casts, intact or replaced.</p> <h2>Specimens</h2> <p><a href="/p1acollections/exhibits/show/corals" target="_blank" rel="noreferrer noopener">Browse corals</a></p> <h2>External links</h2> <p><a href="http://paleosoc.org/wp-content/uploads/2015/08/Corals.pdf" target="_blank" rel="noreferrer noopener">Paleosoc coral info</a></p> radial symmetry