5 10 264 https://wserv3.esc.cam.ac.uk/p1acollections/files/original/74710dbf85be2a6e9e238ba537ef6ad4.jpg 28595880e272b17b8a23671cdc97d677 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>Garnet</h2> Description An account of the resource <div class="element"> <h3>Formula</h3> <div class="element-text">(Mg,Fe,Ca)₃Al₂Si₃O₁₂</div> </div> <div class="element"> <h3>Structure</h3> <div class="element-text"> <p>Orthosilicate</p> </div> </div> <div class="element"> <h3>Crystal System</h3> <div class="element-text"> <p><em>Crystal system:</em><span> </span>cubic</p> </div> </div> <div class="element"> <h3>Physical Properties</h3> <div class="element-text"> <p><em>Colour in hand specimen:</em><span> </span>typically red<br /><em>Cleavage:</em><span> </span>none<br /><em>Hardness:</em><span> </span>6-7.5</p> </div> </div> <div class="element"> <h3>Optical Properties</h3> <div class="element-text"> <p><em>Colour in plane polarised light:</em><span> </span>colourless, pale pink<span> </span><br /><em>Pleochroism:</em><span> </span>none<br /><em>Relief:</em><span> </span>high<br />Isotropic</p> </div> </div> <div class="element"> <h3>Mineral Specimens</h3> <div class="element-text"> <p><span><strong>M130 Garnet schist</strong></span><br /><strong>Portsoy, Banffshire</strong><br />Euhedral porphyroblasts of dark-red garnet, with quartz, mica and other minerals in a medium-grade metamorphic rock.</p> </div> </div> <div class="element"> <h3>Rock Specimens</h3> <div class="element-text"> <p><a href="/p1acollections/exhibits/show/metamorphic-rocks/l504">L504 Garnet schist</a></p> </div> </div> <div class="element"> <h3>Advanced Notes</h3> <div class="element-text"> <p>The garnet group encompasses a wide range of compositions, and consequently a range of optical and physical properties. The properties detailed above are typical of pyrope (Mg₃Al₂Si₃O₁₂), almandine (Fe²⁺₃Al₂Si₃O₁₂) and grossular (Ca₃Al₂Si₃O₁₂).</p> </div> </div> <div class="element"> <h3>Mineral Name</h3> <div class="element-text">garnet</div> </div> metamorphism metapelite https://wserv3.esc.cam.ac.uk/p1acollections/files/original/b8b233edb6e035dc684e24f4623b773c.jpg eccd6795baa14b8a4a88173b5a20e307 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>Epidote</h2> Description An account of the resource <div class="element"> <h3>Formula</h3> <div class="element-text">Ca₂Al₂O∙(Al,Fe³⁺)OH[Si₂O₇][SiO₄]</div> </div> <div class="element"> <h3>Structure</h3> <div class="element-text"> <p>Orthosilicate</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><em>Colour in hand specimen:</em><span> </span>green<br /><em>Cleavage:</em><span> </span>one, perfect<br /><em>Hardness:</em><span> </span>6</p> </div> </div> <div class="element"> <h3>Optical Properties</h3> <div class="element-text"> <p><em>Colour in plane polarised light:</em><span> </span>yellow-green<br /><em>Pleochroism:</em><span> </span>yes<br /><em>Relief:</em><span> </span>high<br /><em>Birefringence:</em><span> </span>0.015-0.051; 1st order orange to 3rd order pink<br /><em>Extinction:</em><span> </span>inclined<br /><em>Twinning:</em><span> </span>lamellar, not common</p> </div> </div> <div class="element"> <h3>Rock Specimens</h3> <div class="element-text"> <p><a href="/p1acollections/exhibits/show/sedimentary-rocks/l354">L354 Limestone, shelly</a></p> </div> </div> <div class="element"> <h3>Mineral Name</h3> <div class="element-text">epidote</div> </div> low grade medium grade secondary https://wserv3.esc.cam.ac.uk/p1acollections/files/original/12b5c18a74215d375e002f21037f4df9.jpg 113d76f170e53159aa1248482d0c7b82 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>Tourmaline</h2> Subject The topic of the resource <span>Tourmaline is the only common mineral of which boron is an essential constituent. Its presence in a rock, therefore, indicates that the rock contains significant boron. </span> Description An account of the resource <div class="element"> <h3>Formula</h3> <div class="element-text">(Na,Ca)(Mg,Fe,Mn,Li,Al)₃(Al,Mg,Fe³⁺)₆[Si₆O₁₈](BO₃)₃(O,OH)₃(OH,F)</div> </div> <div class="element"> <h3>Structure</h3> <div class="element-text"> <p>Ring 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>black<br /><em>Hardness:</em><span> </span>7</p> </div> </div> <div class="element"> <h3>Optical Properties</h3> <div class="element-text"> <p><em>Colour in plane polarised light:</em><span> </span>typically brown-green or green<br /><em>Pleochroism:</em><span> </span>strongly pleochroic in many colours<br /><em>Relief:</em><span> </span>moderate<br /><em>Birefringence:</em><span> </span>typically 2nd order</p> </div> </div> <div class="element"> <h3>Rock Specimens</h3> <div class="element-text"> <p><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">tourmaline</div> </div> granite metapelite pegmatite https://wserv3.esc.cam.ac.uk/p1acollections/files/original/6a2fdeca2774e679a0153821edf123e9.jpg 6a17bfc2d428df30b504c9506a7bb23a https://wserv3.esc.cam.ac.uk/p1acollections/files/original/2711ba062a08634b610c1cdd18f67fcc.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>Orthopyroxene</h2> Description An account of the resource <div class="element"> <h3>Formula</h3> <div class="element-text">(Mg,Fe)₂Si₂O₆</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 system:</em><span> </span>orthorhombic (+) (-)</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><br class="NoSpacing" /><em><span>Cleavage:</span></em><span> two at 90°</span><span> </span><br class="NoSpacing" /><em><span>Hardness:</span></em><span> 5-6</span></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, reddish or greenish </span><br class="NoSpacing" /><em><span>Pleochroism:</span></em><span> variable weak to strong</span><span> </span><br class="NoSpacing" /><em><span>Relief:</span></em><span> moderate </span><br class="NoSpacing" /><em><span>Birefringence:</span></em><span> 0.007-0.020; 1^st order grey to 2^nd order purple</span><span> </span><br class="NoSpacing" /><em><span>Extinction: </span></em><span>straight</span></p> </div> </div> <div class="element"> <h3>Advanced Notes</h3> <div class="element-text"> <p class="NoSpacing"><span>Orthopyroxene has two end-member compositions: enstatite, Mg₂Si₂O₆, and ferrosilite, Fe²⁺₂Si₂O₆.</span></p> </div> </div> <div class="element"> <h3>Mineral Name</h3> <div class="element-text">orthopyroxene</div> </div> mafic 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 https://wserv3.esc.cam.ac.uk/p1acollections/files/original/be33d89fe6d9036ae8352a6f3f9a84ad.jpg c11d5dd9223d779156b594135bba0756 https://wserv3.esc.cam.ac.uk/p1acollections/files/original/6674f7f49c2139327e03ef9b7487f568.jpg 434535ac740cdd1dd8093026a4e67be7 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>Amphibole (hornblende)</h2> Description An account of the resource <div class="element"> <h3>Formula</h3> <div class="element-text"> <p>(Na,K)_0-1Ca₂(Mg,Fe²⁺,Fe³⁺,Al)₅Si_6-7.5Al_2-0.5O₂₂(OH)₂</p> </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 class="NoSpacing"><em><span>Crystal</span></em><em><span> system: </span></em><span>monoclinic (+) (-)</span></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 ~56°</span><span> </span><br class="NoSpacing" /><em><span>Hardness:</span></em><span> 5-6</span></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> pale green, green, light yellow-brown to brown</span><span> </span><br class="NoSpacing" /><em><span>Pleochroism:</span></em><span> yes</span><span> </span><br class="NoSpacing" /><em><span>Relief:</span></em><span> moderate</span><span> </span><br class="NoSpacing" /><em><span>Birefringence:</span></em><span> ~0.02; 2^nd order purple</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> simple, lamellar, common</span></p> </div> </div> <div class="element"> <h3>Mineral Specimens</h3> <div class="element-text"> <p><strong><span>M210 </span></strong><strong><span>Amphibole, hornblende</span></strong><span> </span><br /><strong>Bilen, Bohemia</strong><span> </span><br />Single, black prismatic<strong><span> </span></strong>crystal.<span> </span><br />At the ends of the crystal two sets of cleavage planes are visible, intersecting at ~56°</p> <p><strong><span>M211 </span></strong><strong><span>Amphibolite</span></strong><span> </span><br /><strong>Isle of Coll, Inner Hebrides</strong><span> </span><br />A metamorphic rock consisting almost entirely of crystals of the amphibole hornblende<span> </span><br />Black<span> </span><br />Brilliant lustre<span> </span><br />Two sets of cleavage planes intersect at ~56°</p> </div> </div> <div class="element"> <h3>Rock Specimens</h3> <div class="element-text"> <p><a href="/p1acollections/exhibits/show/igneous-rocks/l102">L102 Hornblende biotite granite</a><span> </span><br /><a href="/p1acollections/exhibits/show/igneous-rocks/l120">L120 Granodiorite</a></p> </div> </div> <div class="element"> <h3>Advanced Notes</h3> <div class="element-text"> <p class="NoSpacing"><span>The amphibole group encompasses a wide range of compositions. Even the hornblendes, which are a sub-group of the amphiboles, encompass a range of compositions (see mineral formula, above). The properties above refer to hornblende.</span></p> </div> </div> <div class="element"> <h3>Mineral Name</h3> <div class="element-text">amphibole<br />hornblende</div> </div> igneous metabasite https://wserv3.esc.cam.ac.uk/p1acollections/files/original/f45fcf901e391b706d58c5a76ce9e0f7.jpg 0b887bd5e1ae09a04261e9bb9af69078 https://wserv3.esc.cam.ac.uk/p1acollections/files/original/daa51ed8284e2f268043c893ed2835dc.jpg 1c07f39572ce1f39720e395b2d729c83 https://wserv3.esc.cam.ac.uk/p1acollections/files/original/f85892ba7ce86764f8dafc18adab40a6.jpg e9b02c931f4847fb3d65e56480cc42d2 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>Mica, muscovite</h2> Description An account of the resource <div class="element"> <h3>Formula</h3> <div class="element-text">K₂Al₄[Si₆Al₂O₂₀](OH,F)₄</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> colourless</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> 2.5-3</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<span> </span><br class="NoSpacing" /><em>Pleochroism:</em><span> </span>none<span> </span><br class="NoSpacing" /><em>Relief:</em><span> </span>low<span> </span><br class="NoSpacing" /><em>Birefringence:<span> </span></em>0.036-0.049; 2^nd<span> </span>order pink to 3^rdorder yellow<span> </span><br /><em>Extinction: </em>straight</p> </div> </div> <div class="element"> <h3>Mineral Specimens</h3> <div class="element-text"> <p class="NoSpacing"><strong><span>M301 </span></strong><strong><span>Mica, muscovite</span></strong><span> </span><br class="NoSpacing" /><strong>Lincoln County</strong><strong>, North Carolina</strong><strong></strong><span> </span><br class="NoSpacing" />Well-formed tabular crystals showing the pseudohexangonal symmetry<span> </span><br class="NoSpacing" />Colourless, mirror- like, metallic lustre<span> </span><br class="NoSpacing" />Platy, flaky habit<span> </span><br class="NoSpacing" />Soft</p> <p class="NoSpacing"><strong><span>M302 </span></strong><strong><span>Mica, muscovite</span>   <span> </span></strong><br class="NoSpacing" /><strong>Mysore</strong><strong>, India</strong><strong></strong><span> </span><br class="NoSpacing" />Plates of mica artificially cut to shape<span> </span><br class="NoSpacing" />Colourless<span> </span><br class="NoSpacing" />One perfect cleavage</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/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">mica<br />muscovite</div> </div> basal cleavage igneous metapelite https://wserv3.esc.cam.ac.uk/p1acollections/files/original/20b9609f2cc656507a1fec2347d9df89.jpg fa472417a23e56ecbb9b556d05c4ffca https://wserv3.esc.cam.ac.uk/p1acollections/files/original/3404979c4792fa74731a7e04e3022017.jpg 599a58e88705064fd972b61f03d15f68 https://wserv3.esc.cam.ac.uk/p1acollections/files/original/65c206021f6f75651f1697f0cd29cf1d.jpg 06b1f7e0df480b95e954641fe6339f67 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>Mica, biotite</h2> Description An account of the resource <div class="element"> <h3>Formula</h3> <div class="element-text">K₂(Mg,Fe²⁺)_6-4(Fe³⁺,Al,Ti)_0-2[Si_6-5Al_2-3O₂₀](OH,F)₄</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 class="NoSpacing"><em><span>Crystal</span></em><em><span> system:</span></em><span> monoclinic (-)</span></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> brown or black</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><span>Colour in plane polarised light:</span></em><span> pale yellow, pale green, green or brown</span><span> </span><br /><em><span>Pleochroism:</span></em><span> strong</span><span> </span><br /><em><span>Relief:</span></em><span> low</span><span> </span><br /><em><span>Birefringence: </span></em><span>0.028-0.08; 2^nd order green-yellow to &gt;4^th order</span><span> </span><em><span><br />Extinction: </span></em><span>straight</span></p> </div> </div> <div class="element"> <h3>Mineral Specimens</h3> <div class="element-text"> <p class="NoSpacing"><strong><span>M303 </span></strong><strong><span>Mica, biotite</span></strong><span> </span><br class="NoSpacing" /><strong>Cornwall</strong><strong></strong><span> </span><br class="NoSpacing" />Large irregular biotite crystals in a feathery arrangement<span> </span><br class="NoSpacing" />Dark brown / black / golden<span> </span><br class="NoSpacing" />Metallic lustre<span> </span><br class="NoSpacing" />Platy habit due to the single perfect cleavage</p> <p class="NoSpacing"><strong><span>M304 </span></strong><strong><span>Mica, biotite</span></strong><span> </span><br class="NoSpacing" /><strong>Orlando</strong><strong>, Canada</strong><strong></strong><span> </span><br class="NoSpacing" />Irregular plates of biotite split along cleavage planes<span> </span><br class="NoSpacing" />One good cleavage<span> </span><br class="NoSpacing" />Brilliant metallic lustre</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 /><a href="/p1acollections/exhibits/show/igneous-rocks/l101">L101 Granite</a><span> </span><br /><a href="/p1acollections/exhibits/show/igneous-rocks/l102">L102 Hornblende biotite granite</a><span> </span><br /><a href="/p1acollections/exhibits/show/igneous-rocks/l120">L120 Granodiorite</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/metamorphic-rocks/l504">L504 Garnet schist</a></p> </div> </div> <div class="element"> <h3>Mineral Name</h3> <div class="element-text">mica<br />biotite</div> </div> basal cleavage igneous metapelite 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 https://wserv3.esc.cam.ac.uk/p1acollections/files/original/6667ec467cbdbb73c1ac797cbd273fd0.jpg 583f6ed4a44b73689a712abe98dec971 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>Serpentine</h2> Subject The topic of the resource <span>Serpentine is a common alteration product of olivine, produced by hydration at low temperatures.</span> Description An account of the resource <div class="element"> <h3>Formula</h3> <div class="element-text"> <p>Mg₃[Si₂O₅](OH)₄</p> </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 or orthorhombic (-)</p> </div> </div> <div class="element"> <h3>Optical Properties</h3> <div class="element-text"> <p class="NoSpacing"><span>Serpentine is commonly very fine-grained. It can be recognised by its textural association with olivine and by its low birefringence and habit.</span></p> <p class="NoSpacing"><em><span>Colour in plane polarised light:</span></em><span> green</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> 1^st order</span></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/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>Mineral Name</h3> <div class="element-text">serpentine</div> </div> alteration hydration olivine