Ricerc@Sapienza

Tourmalines form the most important boron rock-forming minerals on Earth. They belong to the
cyclosilicates with a structure that may be regarded as a three-dimensional framework of octahedra ZO6
that encompass columns of structural “islands” made of XO9, YO6, BO3, and TO4 polyhedra. The overall
structure of tourmaline is a result of short-range and long-range constraints resulting, respectively on the
charge and size of ions. In this study, published data are reviewed and analyzed to achieve a synthesis

Mineral species should be identified by an end-member formula and by using the dominant-valency rule as recommended by the IMA-CNMNC. However, the dominant-end-member approach has also been used in the literature. These two approaches generally converge, but for some intermediate compositions, significant differences between the dominant-valency rule and the dominant end-member approach can be observed. As demonstrated for garnet-supergroup minerals, for example, the end-member approach is ambiguous, as end-member proportions strongly depend on the calculation sequence.

To univocally identify mineral species on the basis of their formula, the IMA-CNMNC recommends the use of the dominant-valency rule and/or the site-total-charge approach, which can be considered two procedures complementary to each other for mineral identification. In this regard, several worked examples are provided in this study along with some simple suggestions for a more consistent terminology and a straightforward use of mineral formulae. IMA-CNMNC guidelines subordinate the mineral structure to the mineral chemistry in the hierarchical scheme adopted for classification.

A new, IMA-approved classification scheme for the spinel-supergroup minerals is here reported.

A green tourmaline sample from the Tzarevskoye uranium–vanadium deposit, close to the Srednyaya Padma deposit, Lake Onega, Karelia Republic, Russia, has been found to be the second world-occurrence of Cr-rich vanadio-oxy-dravite in addition to the Pereval marble quarry, Sludyanka crystalline complex, Lake Baikal, Russia, type-locality. From the crystal-structure refinement and chemical analysis, the following empirical formula is proposed: X(Na0.96K0.02□0.02)Σ1.00 Y(V1.34Al0.68Mg0.93Cu2+0.02Zn0.01Ti0.01)Σ3.00 Z(Al3.19Cr1.36V0.03Mg1.42)Σ6.00(TSi6O18)(BBO3)3V(OH)3W[O0.60(OH)0.23F0.17]Σ1.00.

The classification of the tetrahedrite group minerals in keeping with the current IMA-accepted nomenclature rules is discussed. Tetrahedrite isotypes are cubic, with space group symmetry I 4 ̄ 3m. $Ioverline43m.$The general structural formula of minerals belonging to this group can be written as M(2)A6M(1)(B4C2)X(3) D4S(1)Y12S(2)Z, where A = Cu+, Ag+, o (vacancy), and (Ag6)4+ clusters; B = Cu+, and Ag+; C = Zn2+, Fe2+, Hg2+, Cd2+, Mn2+, Cu2+, Cu+, and Fe3+; D = Sb3+, As3+, Bi3+, and Te4+; Y = S2- and Se2-; and Z = S2-, Se2-, and o.

Medical device (MD) nomenclatures are essential for
market surveillance and vigilance activities. Currently, more
than 25 arthroplasty Registries are established in Europe, each of
them based on a different MD nomenclature. A common and
shared nomenclature of orthopaedic implants is important to
analyse implant performance across different national databases
referring to a unique definition of its characteristics. Aim of this
study is to describe an approach to compare and harmonise two

Plantago Linnaeus (1753: 112) (Plantaginaceae) is a genus including 200–250 species distributed throughout the temperate
zone and the high-elevation tropical regions (Rahn 1996, Rønsted et al. 2002).
This genus is critical from the taxonomical point of view, showing a high morphological variability and plasticity
(Anderson et al. 2013), a reduced number of morphological characters (Rahn, 1996) and a phylogenetic history not completely
resolved (Rønsted et al. 2002, Ishikawa et al. 2009, Tay et al. 2010, Meudt 2011). In addition, recently new species were

The typification of the names Valeriana celtica, V. saxatilis and V. sibirica is discussed. Specimens from UPS and an illustration by Amman are designated as the lectotypes.

Plantago Linnaeus (1753: 112) (Plantaginaceae Juss.) is a cosmopolitan genus including about 250 species distributed
in the temperate zone and high-elevation tropical regions (Pilger 1937, Rahn 1996, Hassemer et al. 2016). The genus
is taxonomically critical because of its high morphological variability and plasticity, reduced number of diagnostic
characters and a still unresolved phylogenetical history (Rahn 1996, Rønsted et al. 2002).
According to the current concept (Rahn 1996, updated by Rønsted et al. 2002, and Hoggard et al. 2003), Plantago