This paper reports on an integrated analytical approach for the noninvasive characterization of Chinese nephrite samples, encompassing both geological reference specimens and museum objects. Natural variations induced by cationic substitutions, as well as human-induced alterations such as heating, which both affect color, are the focus of this contribution. Totally noninvasive methods of analysis were used, including X-ray fluorescence spectroscopy, Raman microspectroscopy, visible reflectance spectroscopy and X-ray diffraction; moreover, the feasibility of using a portable Raman spectrometer for the in-field identification of jades has been demonstrated. Fe/Fe+Mg (% p.f.u.) ratios of the jades have been calculated based on hydroxyl stretching Raman bands, which will provide an important addition to similar data that are being collected at major museums in the Western and Eastern hemispheres.

Background: Architectural fragments of decorated walls, floors, and columns excavated by Ernst Herzfeld at the archaeological sites of Persepolis and Pasargadae in Iran are housed in the Freer Study Collection at the Freer Gallery of Art and Arthur M. Sackler Gallery (FSG), Smithsonian Institution in Washington, DC. Technical studies of these painted earthen plasters and glazed brick fragments were undertaken to enhance our knowledge of materials and technology of Achaemenid Persia between the late sixth and fourth centuries BCE. Initial analysis was done on the surface of the fragments using non-invasive X-ray fluorescence with a portable instrument. Polished crosssections were used to examine the layering stratigraphy of paints and glazes, and to undertake compositional analysis using scanning electron microscopy with energy-dispersive X-ray spectroscopy.Results: Up to five layers of paint are present on the Pasargadae plaster, constituting the remnants of a geometric design. The plasters were bound with clay tempered with an organic material that has long since degraded, leaving small voids throughout. Pigments identified include Egyptian blue, malachite green, red ocher, and cinnabar red. The floor fragments from Persepolis were finished with a lime plaster and two layers of hematite-rich paint. The brick fragments from Persepolis were found to be composed of high-silica material similar to faience, which were decorated with alkaline glazes, including a yellow glazed colored with lead antimonate, gray glaze colored with magnesium and iron, and green glazed colored with copper. Conclusions:While the exact ages of the finishes are unknown, a similar technology was employed to decorate Achaemenid architecture in its principle Iranian cities. The variety of materials excavated by Herzfeld demonstrates the ability of Achaemenid artisans to work with multiple mediums to create a polychromatic finish including that of glazed tiles, earthen plaster tempered with gravel, earthen plaster tempered with organic matter, colored earths, pigmented paints and lime plasters. The layering of these materials can be seen and analyzed in cross-section although surface deterioration is often quite severe. The analysis of the compositional data on the architectural fragments inform their long-term preservation at the FSG as well as at the sites themselves.

The use of metal ions to harden the tips and edges of ovipositors is known to occur in many hymenopteran species. However, species using the ovipositor for delivery of venom, which occurs in the aculeate hymenoptera (stinging wasps, ants, and bees) remains uninvestigated. In this study, scanning electron microscopy coupled with energy-dispersive X-ray analysis was used to investigate the morphology and metal compositional differences among aculeate aculei. We show that aculeate aculei have a wide diversity of morphological adaptations relating to their lifestyle. We also demonstrate that metals are present in the aculei of all families of aculeate studied. The presence of metals is non-uniform and concentrated in the distal region of the stinger, especially along the longitudinal edges. This study is the first comparative investigation to document metal accumulation in aculeate aculei.