Deep Sea Drill Core 25 GARDEN LEVEL EXHIBITS Chrysotile Asbest os Asbestos is not the name of a specifc mineralit is a commercial term for a group of silicate minerals that readily separate into thin strong fber s that are fexible heat resistant and c hemically iner t Chrysotile and tremolite are two minerals that were commonly used in asbestos Asbestos w as widely used in a variety of industrial products though rarely now because asbestos has been found to be carcinogenic This specimen is from S alt Ri ver Can yon Ariz ona Gift from Harrison Cobb Boulder Colorado P olished Ser pentinit e Spher es S erpentine is a sof t massi ve metamorphic roc k It is composed mainly of two serpentine minerals antigorite and c hrysotile S erpentine frequently used as a decorati ve roc k has slic k smooth surfaces S eams and veins of fbrous c hrysotile are mined for use in freproof materials S erpentine gets its name from the snak eskin appearance of sleek greasy multicolored serpentinite roc k surfaces F rom W illiams Quarry Easton P ennsylv ania shaped b y BF Shepherd IngersollRand Co Gifts from Lafa y ette College Easton P ennsylv ania through Arthur Montgomery and P aul J Roper in honor of Lafa y ette alumnus Edwin B Eck el Sider it e with Goethit e Siderite is a minor ore of iron Its shin y brown reddish brown gray or white crystals of ten are curved Siderite becomes blac k and magnetic when it is heated In this specimen goethite has formed as an alternation product on the bladed siderite crystals It may be from the Gilman mining district in Eagle County Colorado where siderite is common in masses and as a lining in cavi ties in the roc ks Siderite forms in a variety of en vironments It forms masses or concretions in clay coal seams and shale It occur s with sulfde minerals in h ydrothermal veins with silver lead and copper ores It is found as a replacement deposit in limestones that have been altered by ironbearing solutions It is also found in a few igneous roc k types including pegmatite Siderite gets its name from the Greek sideros iron Deep Sea Dr ill Cor e This section of drill core w as collected during the Deep S ea Drilling P roject at Site 1 69 southwest of Haw aii at latitude 1 0402 N longitude 1 73330 E It w as reco vered in 5407 m 1 7 7 40 f t of w ater at a depth of 1 87 m 61 4 f t below the sea foor The dark igenous roc k solidifed from magma with high iron and mang anese content This roc k intruded into Cretaceous sedimentary layer s that were deposited at the bot tom of the ocean P er manent loan from the National Science F oundation through W R Riedel curator Deep Sea Drilling Project F ulgur it e This roc k w as formed when a 500 0 0v olt power line fell apar t during a storm near Gold Hill west of Boulder Colorado The electricity fowed through the wet grus crumbly decomposed granite and fused it The white c hunks are pieces of feldspar one of the main minerals of granite F ulgurites are usually formed by lightning Gift from Mary C Eberle