WindSculpted Boulder 21 GARDEN LEVEL EXHIBITS Nativ e Sulfur with Celestit e This specimen comes from Sicily where fne crystals of nati ve sulfur yellow occur in association with celestite and other minerals Nati ve sulfur is a minor ore of sulfur and celestite is the principal ore of strontium Strontium is used to mak e specialty glass glaz e enamel caustic soda and in the processing of sug ar beets It is also used in strontium nitrate whic h produces the bright crimson fame in freworks and signal fares Strontium is also used in bat ter ies paints rubber w axes refrigerant solutions and pharmaceuticals Gift from the Department of Geolog y Univ ersity of T ennessee Kno xville through Otto C K opp A g at e Slab This slab of ag ate polished on both sides is from Brazil Fluids ric h in dis solved silica flled a cavity in basalt roc ks and lef t behind this ag ate The hori z ontally layered fnegrained silica w as deposited layer by layer from solu tion The crystalline quar tz flled the remainder of the cavity later Purchased b y the Society WindSculpt ed Boulder of Cher t and Dolomit e The alternating layer s of dark er c her t and light dolomite were worn down by windblown sand silt and mois ture Cher t is more resistant to weathering so the c her t layer s stand out as polished ridges Dolomite is more soluble and less resistant to weathering it forms the indented layer s Spodumene Crystal This crystal from Minas Gerais Brazil is of gem quality spodumene Spodumene is c haracteriz ed by long fat crystals with deep lengthwise groo ves and an uneven splintery surface The sharply de fned c hange in color near the center of the crys tal is especially rare Spodumene occur s in white to green prismatic crystals of ten of great siz e It tak es its name from the Greek spodumenos burned to ash in reference to the ash y colored woodlik e appear ance of its weathered surfaces The pink gem variety is known as kunzite af ter GF K unz a noted American gemologist Gift from Ra ymond M Thompson Engle w ood Colorado F ossil Br ac hiopod Brac hiopods have li ved since the early P aleoz oic Although most forms are extinct one branc h has survi ved to modern times Brac hiopods were at their peak during the middle and late P aleoz oic about the time this brac hiopod w as ali ve They li ved at tac hed to roc ks shells or other hard surfaces at the bot tom of the sea Gift from Xu ZhengLiang East China Geological Institute T our malineCement ed Br eccia This unusual breccia from the Cananea mining district in S onora Mexico forms a ring around a copper and silver ore body It contains fragments of v olcanic rh yolite and igneous quar tz monz onite porph yry all cemented by blac k tourmaline The feldspar bearing roc k fragments are veined by quar tz Gift from Compania Minera de Cananea SA de CV courtesy of Guiller mo A Salas Cananea Me xico