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Many more pseudomorphs are nucleated from the azurite matrix interface than nucleated from the azurite crystal surface. In conclusion, the analysis of these pseudomorph illustrations suggests the following: Azurite can continue to grow on azurite while malachite pseudomorphs are growing within. The four azurite crack surfaces have conchoidal fractures on one surface, complete coverage of new secondary azurite on a second surface, and two vertical surfaces with mixed conchoidal areas and new azurite. The governing reaction for malachite growth is: Two azurites plus one water yields three malachites plus carbon dioxide. [Extracted from the article]

Most of the micromineral inclusions generated by the RMR process in Schickler apatite appear to be REE minerals; an example EDS spectrum of a typical REE inclusion is shown in figure 2. The I T i I O i I T i modules within these minerals can be used to derive many mineral properties by first principles, e.g., habit, cleavage angles, and symmetry/polytypism (fig. 1). Among other minerals, striking red-brown apatite crystals, to 10+ cm, can be found hosted within the dissociated calcite-fluorite carbonatite matrix. However, the diversity of these modular rock-forming minerals results in complexity in terms of the crystal structures and crystal chemistries of this mineral family. [Extracted from the article]

The acicular quartz was the first mineral to form, and crystals can be found protruding from quartz of normal morphology that grew around them. This would lead to the change from earlier crystallizing As-bearing sulfide minerals (arsenopyrite) to later-forming arsenide minerals (löllingite) in the core zone as the sulfur anions became depleted. The pegmatite has the highest mineral species count, currently 183 (Falster et al. [2]), in the state of Maine. [Extracted from the article]

PHOTO (COLOR): RMS Program Cover by Susan Robinson THE THIRTY-SEVENTH TECHNICAL SESSION of the Rochester Mineralogical Symposium was cancelled this year due to the COVID-19 virus. By experimenting with the addition of mica of varying thickness to the optical path when viewing a flattened gahnite and garnet in crossed polars, we found that the observed interference figure was the result of the mica even when exceedingly thin. Multiple flattened almandine crystals have also been extracted from muscovite books from Avondale, Pennsylvania. White included the results of optical analyses performed by our research group on a flattened gahnite, which showed that the crystal exhibited a distinctly biaxial interference figure despite being an isometric mineral. [Extracted from the article]

Heavy mineral separation reveals the presence of garnet-group minerals and magnetite as well as native gold. Magnetite crystals display the same variability in transport indicators as garnet, and there is a notable decrease in the size of individual crystals and the proportion of magnetite between samples relative to their downstream position. Crystals of smoky quartz and amazonite are present as well as a number of accessory minerals, including several beryllium mineral species. The single-crystal diffraction data of eight plutonic labradorite crystals and one metamorphic labradorite crystal show that they all have the incommensurately modulated structures, characterized by the satellite reflections ( I e i -reflections), which cannot be indexed by integer Miller indices. [Extracted from the article]

When the ginseng collector is also a mineral collector, new exposures of interesting minerals occasionally turn up. This has led to a long and fruitful collaboration between amateur collectors and professional mineralogists who have described more than four hundred different mineral species and sixty-six new or type-locality minerals from this small quarry in Quebec. The minerals found at this exposure are distinct from those found a mere 90 meters south at the Wollastonite Skarn (WSK), the classic mineral occurrence at Rose Road. The mineral specimens recovered in the years that followed the discovery of the PDM have conveyed a fascinating and complex paragenesis involving numerous different types of pseudomorphs and mineral textures. [Extracted from the article]

The article offers information on the papers presented during the 41st Rochester Mineralogical Symposium held in Michigan on April 24-27, 2014. Topics discussed in the symposium included metamorphic minerals from the Alta Aureole, Central Wasatch Mountains, Utah, and a new mineral, steedeite from Mont Saint-Hilaire, Quebec.

One spodumene crystal exceeded 11 meters in length, and crystals in excess of 2 meters in length are common. It is spodumene-rich with more than 50 percent spodumene in some of the upper portions of the pegmatite. These spodumene and montebrasite crystals are comparable in size to the famous crystals from the Etta and Hugo pegmatites in South Dakota, where 14-meter spodumene crystals and 7-meter amblygonite (likely montebrasite) occur (Rickwood [1]). [Extracted from the article]

The article offers information on various contributed papers in Specimen Mineralogy on the twenty-first, twenty-second and twenty-third session of the Rochester Mineralogical Symposium (RMS). Every year, the review panel is composed of Carl Francis of Harvard University, George Robinson of Michigan Technological University and Robert King of Tewksbury, Great Britain, among others. "Development of Growth Pits on Carrollite From Kamoya II Open Pit in Katanga, Congo," R. Morgan, offers information on the processes involved on the progress of growth pits.