...Bryan C. Chakoumakos; Brenda M. Pracheil Abstract Vaterite occurring in fish otoliths exhibits plumose and spherulitic habits, the latter being like those grown from aqueous solutions. Vaterite spherulites are known to have sheaf-like texture and can be up to 100 μm in size. In thin section...

... behind a concentration of megacrysts around this pocket. The orbicule structure of concentric shells with radial and tangential crystal habits and the reverse zoning of the plumose plagioclase are evidence of disequilibrium conditions during crystallization of the orbicules. The radial growth...

... and London 1999 ). In the layered aplite, the fine-grained aplite represents rapid crystallization (high nucleation rate, high growth rate) from the undercooled magma. Rapid crystal growth of the undercooled melt is indicated by the dendritic or plumose habit of the alkali feldspar, quartz, and biotite...

... of the matrix and the fine-grained to pegmatite volume ratio. The shell is made up of radiating plumose K-feldspar megacrysts ( Fig. 3 ), up to 5 cm in size, which grew orthogonally to the nucleus boundary; their habit is very reminiscent of K-feldspar in marginal pegmatites with a comb structure (so...

.... The Lower Mound is a boundstone composed of plumose masses of algal and foraminiferal material, with entwined dasycladacean algae and small pelecypods ( Fig. 5 ). This boundstone facies is the shallow-water climax community of an earlier organic buildup. The encrusting and binding growth habit of the algal...

... familiaris ) by BND confirmed they are distinct from Melittosphex burmensis in a number of important morphological features. The Myanmar amber pemphredonines all lack branched, plumose hairs visible under high magnification on Melittosphex , they lack a pygidial plate, they have an elongate pronotum...

... of specimens, collectively permitting analysis of its morphology, growth mode, and life habits. Bradgatia is a petalage that consists of a radial array of up to eight petals, each exhibiting up to four visible orders of rangeomorph branching. The taphonomy and ontogeny of Bradgatia are tightly linked...

... A1, griffe G2 de type couteau, formes des organes de serrage et de l’hémipénis) et de la structure de la carapace (par exemple, VG avec extension, RV avec postérieur denticules). Dans l’ensemble, les espèces vivantes signalées ici semblent habiter relativement chaudes (15–30 °C) dans les plages...

...Gennaro Ventruti; Francesca Stasi; Daniela Pinto; Filippo Vurro; Monica Renna Abstract We deal with a single-crystal X-ray diffraction study of boulangerite from a plumose sample from the Bottino mine, Apuan Alps, Italy. Chemical composition of the analyzed sample is Pb 4.89 (Sb 4.08 As 0.04 Bi...

... interior, producing a siphuncle band. The skeleton was produced by a deep-bodied animal of demersal life habits. The species B. uncinata , B. harrisi and B. alabamensis voltzi proposed by Palmer (1937) are synonymised with B. ungula . The species B. veatchii and B. saccaria of Palmer (1937) are considered...

...Fig. 4. Raman spectra obtained from solid phases in the crystal-rich inclusion shown in Figure 3 a. Cookeite was identified by its low retardation and plumose or sheet-like crystal habit ( Fig. 3 b and 3 d) and by a Raman OH stretching frequency at ∼3640 cm –1 . Characteristic Raman vibration...

... that garnierite is mostly constituted by plumose aggregates made of curved crystals with frayed tips, a few nanometers thick along the stacks and a few tens of nanometers long (nanoflakes). All known lizardite stacking sequences, namely 1 T , 2 H 1 , and 2 H 2 , have been locally observed, even though most...

... or flamboyant habit (cf. Dong et al., 1995 ). Figure 8B shows a better example of flamboyant quartz, with radial extinction of individual grains in a colloform band. Plumose textures are also present in the central to lower central part of Figure 8C . These textures are associated with sericite that occurs...

..., and that the similarity with other members of the Nama-type biota reflects convergence in functional and fabricational constraints in relation to infaunal life habit. In the course of a study of Pteridinium Gürich, 1933 , we have tested an infaunal model with three-dimensional preservation (see Grazhdankin...

... 0.5 to 3 mm long and is associated with quartz exhibiting drusy, comb, plumose, zonal, bladed, and cockade textures ( Fig. 10E, F ). Wolframite-bearing breccias and quartz veins crosscut zones with copper sulfides of stage 3. Clasts of previous brecciation events are in wolframite-bearing quartz...

... a 3-D model. However, this series of images also reveals the general growth habit of the chambers ( Fig. 3 e–g). All studied samples and thin-sections are archived at the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences. The exposed part of the Donglongtan...

... titanian phlogopite, prismatic ilmenite (black) set in a colourless matrix consisting of K-feldspar and quartz. Plane polarized light (PPL). ( b ) Lamproite Raniganj GL-4, showing microphenocrystal ilmenite (Ilm), apatite (Ap) and clinopyroxene (CPX) set in a groundmass of plumose-textured prisms of K...

... or plumose hypothallium and a perithallium that contains strongly developed vertical and horizontal threads formed of cells ∼5 µm wide by ∼5 µm high (Fig. 5D) . Vertical stacks of 5–6 megacells are common throughout the perithallium. Laminar crusts of Neogoniolithon sp. have a constant thickness apart...

... in a hextetrahedral habit with three main crystallographic forms ({100}, {111}, and {010}; Fig. 3a ). In this study, no acicular or wurtzite-like texture as previously shown by Pring et al. (2020) , has been imaged by EBSD. In the four studied sphalerite types, EBSD maps show large grain size variations ( Fig. 3b...