A project which incrementally extends pbrt is described. Example scenes showing Fresnel reflection, isotropic absorption, and pleochroism in the gemstone tourmaline are presented. Tourmaline is typical for absorption characteristics in crystals, characteristics which often vary with wavelength and direction. Interesting color and intensity variation results from splitting incident rays, by pola...

Planar, rigid glass substrates support the formation of organic small-molecular semiconductor thin films with extended crystalline texture and distinct pleochroism (top in cover picture), visible by cross-polarized microscopy. Woven, soaking electrospun nanofiber mat disrupt growth, leading to submicron-sized crystallites embedded fiber mesh (bottom). The benefits tissue-like mats are that they...

Polycrystalline textured thin films with distinct pleochroism and birefringence comprising oriented rotational domains of the orthorhombic polymorph an anilino squaraine isobutyl side chains (SQIB) are analyzed by imaging Mueller matrix ellipsometry to obtain biaxial dielectric tensor. Simultaneous fitting transmission oblique incidence reflection scans combined spatial resolution optical micro...

The Alto Quixaba pegmatite, Seridó region, northeastern Brazil, is a 60 degrees/80 degrees SW-trending subvertical dike discordantly intruded into biotite schists of the Upper Neoproterozoic Seridó Formation. It has three distinct mineralogical and textural zones, besides a replacement body that cuts the pegmatite at its central portion and in which occur, among other gem minerals, colored elba...

Three samples of fluorapophyllite-(K) with different cation composition were studied by the X-ray diffraction and IR-spectroscopy methods. The (K0.72(NH4)0.20)Σ0.92Na0.08 Ca4[Al0.04Si7.96O20]F·8H2O from Nidym K0.87Na0.06 Ca4[Si8O20]F·8H2O Akhaltsykhe localities are characterized deficiency large cations K+ (NH4)+ in A site; chemical Talnakh sample (K0.94(NH4)0.06)Σ1.00 is close to stoichiometri...