مجله بلور شناسی و کانی شناسی ایران
سال هفتم شماره 1 (پیاپی 14، بهار و تابستان 1378)

Milshhad ~fani l c and l!,funodinrilcs arc inlfUlkd in th ree different period between Triass ic to Lue JU fllssic. Muscovi te- biotitl! gr:tn itc and pegmatill!s (the you nge ls) arc exposed be tween Khal adgc ,md Khaj c h Mourad area. Alkali fe ld spars within pegmatite d ykes. between G hcshlagh, iloll Khladgc, we re sludit!d in detai l inclucJing l}rC rese rve es ti mation. mineralogy. chemical composition. and industrial uses. Fddspar in the Gheshlagh area is K-rich type (K20>%9 and Na.p< %2). While in Kbajch Moufild lIrC<I. hoth types of K lind NlI -rich fe ldspa rs arc recognized, "chr('39')~ Ghcshlagh feldspar Lchr('39')i suitable for ceramic body and the N,Hich type I:rom Khajeh Mourad is applicable in glass and as filler in paint and rubber industries.

A software in fortran is developed to determine crystal structure of cubic. tetragonal. hexago nal and orthorhombic crystals from powder ditTraction d values. The general 1t6s method is also used for triclinic and monoclinic crystals.

The Mozduran One Formation (Middle Jura~!;ic ) in NE Ma!;hhad is mainly composed o f dolomite and limestone. Based on texture (size and fabri c), dolomites were divided into 5 diITerent types with a crystal size which ranges from 10 to 1200 microns. Type one is very fine tn fine subhedral to euhedral crystals. while type two is fine to medium euhedral with poikilotopic texture. Type three is medium planar suhhedralto anhedral crystals with idintopic texture. Type four is medium to coarse anhedral nonpianar crystals and type five is coarse with dolomite cement. Distinction between types 3 and ,1 is difficuil and is mainly based on the larger number of crystal hthliidries in type three and stronger undulose extinction in type four. Dolomite.chr('39')I of types nne to three are mainly formed in the early stages. while types 4 and 5 formed during the burial. in the late stages of the diagenetic history of the rock. It is concluded that bachr('39')led on texture. dolomites can be divided into different types and thereby the ir origin can be interpreted.

The Crystal Structure of I <It • (bcnzoylmc thyl) benzyll Silane (CH3h Si CH (C(> H ~ )CH2 COC(>Hs has been determined by direct method (Sir). The dimensions of used cry:,tal were 0.7 x 0.3 x 0.2 mm. TIle molecular structure has been determined by MolEN program. This compound crystalizc.s in monoclinic space group P2t /n (14) with four molecules per unit cell. Lattice parameters of this compound an.:: :a = 6.0938 A. h = 22.8465 A. c = 12.0533 A. p= 92.0605chr('39') Afll.::r lasl least· square cycle, lht.! final R anJ R.,... values are 0.087 and 0.093 , re.spectively.

this study is focused on do lomi te s of the Chehel-Kaman Formation (Upper Paleocene) that is located in NE Iran. Field and petrographic studies lead to distinguish dl and d2 dolomites. dL is fine crystals (Ie.<;ser than 10 micron) and is associated with t:vaporatic sed ime nts. and d2 in addition to fint: crystals. contains coarser crystals (50-RO micron) without evaporatic sediments. Also. oxygen isotope of ell is hCltvicr than -2.5 %" PDB and oxygen isotope of d2 is lighter than - 6.5 %0 PDB. Cchr('39')lrbon isotope in these dolomites ranges between + 1.8 %0 to +3.5 %0 PDB. These data along with CL o bse rvation show that d l dolomites are formed in lower temperature (calculated temperature is 26°C) within supratidal environment, while d2 dolomites are formed in higher temperature (calculated temperature is more than n °C) during burial stage.