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Abstract: In order to obtain full information coverage on melt inclusions in Martian meteorites (subgroup nakhlites) complementary micro-analytical techniques were used, i.e. focused ion beam, transmission electron microscopy and laser ablation. Using focused ion beam several lamellae for transmission electron microscopy were prepared and secondary electron images of cross-sections could be acquired. Laser ablation–inductively coupled plasma mass spectrometry analyses were performed on selected inclusions to obtain mass-oriented bulk composition of inclusions at depth. The differences in composition between melt inclusions in olivine and augite crystals would suggest a xenocrystic origin for olivine. Furthermore, electron diffraction patterns clearly indicated that the SiO2-rich phase in inclusions from augite in meteorites from Northwest Africa site is re-crystallized, whereas it is still vitreous in the inclusions from Nakhla sampling site. Therefore, different post-entrapment evolutions were active for the two nakhlite meteorite sets, the Nakhla and the NWA817 set. Melt inclusions in Nakhla olivine presented alteration veins, which were presumably produced before their landing on Earth. If this is the case, this would indicate a alteration stage already on Mars with all the consequence in terms of climate history. Melt inclusions in Nakhla augite resulted unaffected by any alteration or modification following the entrapment, and therefore represent the best candidate to indicate the pristine magma composition. [Copyright &y& Elsevier]

The article describes a deposit of yellow-to-orange quartz discovered by Jean-Claude Nydegger in northern Minas Gerais State in Brazil. According to Nydegger, the sample features some quartz veins which contain transparent-to-opaque areas that varied from white to yellow-orange. Upon closer analysis, some thin bands with yellow-orange color. Although approximately 1,500 kilograms of quartz were taken from the veins, only 5 kilograms of the quartz was gem quality. The color of the quartz vary from pale yellow to yellow or orange based on the abundance and color of the needles.

This article explores the characteristics of ankangite and celsian inclusions in quartz from Brazil. It identifies the properties that were obtained from an examination of the samples. It discusses the results of standard gemological techniques, scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS), and electron microprobe analysis of the samples. It notes that the presence of both ankangite and celsian inclusions in this quartz suggests that it originated from a barium-rich deposit.

The article presents information on a new gemstone from Italy called Violan quartz. Violan is an obsolete term for violet-to-blue. The only known localities for this type of clinopyroxene is the Praborna mine, located near Saint-Marcel in Aosta Valley, northern Italy. Violan, also known from southern Baffin Island, Nunavut, Canada, is found as massive aggregates in calc-silicate lenses. Violan is being collected because of its rarity and deep violet color. An Italian geologist presented two pear-shaped cabochons of colorless quartz with violet inclusions at the Verona Mineral Show in May 2007. Using gemological techniques and electron-microprobe analysis of the quartz, the violet inclusions were identified as violan.

The article offers information about the fluorite presented by Tesfay Desta, an Ethiopian dealer, at the Bologna Mineral show in Italy in March 2007. The fluorite was said to have been obtained from a mine in the Guji zone, southern Ethiopia. Five crystals were examined and crystallized. The gem material was identified as a fluorite based on data from X-ray powder diffraction. Desta brought 25 kilograms of rough Ethiopian fluorite during the Verona mineral show in May 2007. Some of them are color-change.

The article describes a rutilated quartz doublet acquired from a trip to Teófilo Otoni, Minas Gerias, Brazil in September 2005. Examination of the stone was conducted after doubting its authenticity due to its low price and preliminary visual inspection. Refractive indices revealed they are quartz but when viewed from the inside they were doublets. It features a thin layer of semitransparent rutilated quartz joined by a transparent adhesive. When the samples were immerse in water, their assembled nature were more evident.

The article discusses the results of the examination of two loupe-clean rough samples which were said to be Imperial topaz at the Department of Earth Science of the University of Rome La Sapienza in Rome, Italy. No fluorescence was observed when exposed to long- and short-wave ultraviolet (UV) radiation. Gemological data revealed that the specimen were corundum. Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) detected the presence of several elements nickel (Ni), titanium (Ti) and magnesium (Mg).

This section offers precious stones news briefs. Bill Larson and Steve Ulatowski revealed a green grossular from Tanzania that stands out for its transparency and good color. Nirvana Stone of Japan started to market a variety of quartz under the name Anandalite during the 2011 Pueblo Gem & Mineral Show. Eight specimens of transparent yellowish brown pargasite was donated by G. Scott Davies to the Gemological Institute of America (GIA) in 2011.

Bivalirudin, a direct thrombin inhibitor, is as effective as unfractionated heparin (UFH), with decreased bleeding in patients with acute coronary syndromes who undergo percutaneous coronary intervention (PCI). The aim of this study was to evaluate the effectiveness of bivalirudin versus UFH in selected PCI patients at high bleeding risk. Four hundred one consecutive patients who underwent PCI fulfilling ≥1 enrollment criterion (age >75 years, chronic renal failure, and diabetes mellitus) were randomized to bivalirudin (bolus 0.75 mg/kg followed by infusion during the procedure; n = 198) or UFH (75 IU/kg; n = 203). In the overall population, 39% were aged >75 years, 22% had renal failure, 63% had diabetes, and 29% had acute coronary syndromes. The primary efficacy end point was the 30-day incidence of major adverse cardiac events (cardiac death, myocardial infarction, stent thrombosis, or target vessel revascularization). The primary safety end point was the occurrence of any bleeding or entry-site complications after PCI. All patients were preloaded with clopidogrel 600 mg. Glycoprotein IIb/IIIa inhibitors were used at the operators'' discretion. Thirty-day major adverse cardiac event rates were 11.1% in the bivalirudin group and 8.9% in the UFH group (p = 0.56); the primary efficacy end point was reached mainly because of periprocedural myocardial infarction; 1 patient in the bivalirudin group had stent thrombosis. Occurrence of the primary safety end point was 1.5% in the bivalirudin group and 9.9% in the UFH group (p = 0.0001); this benefit was essentially driven by the prevention of entry-site hematomas >10 cm (0.5% vs 6.9%, p = 0.002). In conclusion, Anti-Thrombotic Strategy for Reduction of Myocardial Damage During Angioplasty–Bivalirudin vs Heparin (ARMYDA-7 BIVALVE) indicates that bivalirudin, compared with UFH, causes significantly lower bleeding and has a similar incidence of major adverse cardiac events in patients with older age, diabetes mellitus, or chronic renal failure who undergo PCI. [Copyright &y& Elsevier]

This section offers news briefs related to gems and gemology. The Tucson Gem and Mineral Society show was held in 2010 with the theme "Gems and Gem Minerals." Several small orangy pink round brilliants that were submitted for color origin identification were examined by the Gemmological Association of All Japan at Zenhokyo Laboratory. A unique decorative prayer rug gemstone was recently encountered by the Gübelin Gem Lab.