Efflorescence, subflorescence, and crust weathering …

In the H2SO4 acid leaching test, efflorescence pattern was the most likely type of decay in yellow and cyan sandstones. Thenardite was the exclusive salt in the yellow sandstone, while gypsum was the mainly salt in the cyan sandstone. Gypsum crust and subflorescence were the most common types of decay for gray sandstone.

THENARDITE |

Thenardite and calcite are also present mainly along the icerock interface. Nobuyuki NAKAI, Yoshihiko MIZUTANI, Hideki WADA 1977, ' Volcanic Events of Ross Island, ... The cored sediments were found to contain layered salt concretions composed of gypsum, thenardite and calcite. Nobuyuki NAKAI, Yoshihiko MIZUTANI 1977, ' Geological …

SEM micrographs (at 5000×) of sample 5NS showing: (a) gypsum…

Download scientific diagram | SEM micrographs (at 5000×) of sample 5NS showing: (a) gypsum; (b) thenardite; and (c) AH3. from publication: Effect of Alkaline Salts on Calcium Sulfoaluminate ...

of thenardite (Na2S04) and gypsum (CaS04 • 21120) was often observed as one of the main causes of the fragilization and the flaking of the bricks. The salt crystallization was observed more heavily on the bricks under the southern …

Multitechnique characterization of secondary minerals near …

These secondary minerals, encompassing calcite, silica speleothems, gypsum, and thenardite, commonly originate as a consequence of seepage waters infiltrating the lava tube system, dissolving ...

PRECIPITATION OF LAUMONTITE WITH QUARTZ, …

scanning electron microscope (SEM), and electron microprobe analyses show thenardite to be the dominant phase in the exterior coatings, in association with minor microcrystalline «50 /Lm) laumontite and gypsum. Macrocrystalline (> I mm) laumontite is the dominant phase in interior fracture coatings and is associated

GLAUBERITE (Sodium Calcium Sulfate)

Glauberite forms in saline environments with other evaporite minerals such as halite, gypsum, calcite and thenardite. Modern as well as prehistoric evaporite deposits can have glauberite crystals. Some glauberite has been identified in sublimate deposits on lavas off the coast of Sicily. Hydrothermal precipitation of glauberite is also seen.

Use of Gypsum as a Preventive Measure for Strength …

Considering that the activating solution for F-NW produces ~2.2 moles of Na + per 1 kg of fly ash, 2% gypsum addition can temporarily reduce the availability of Na + by retaining up to ~11% Na + in the form of thenardite. In the same way, 4% and 6% gypsum additions could reduce the Na availability by up to ~22% and ~33%, respectively, in the ...

Sodium sulphate deposits of Neogene age: the Kirmir …

Thenardite facies in the galleries of the Çayirhan mine (A–D), mirabilite texture (E), and secondary gypsum textures (F and G). (A) Thenardite layers. Hammer …

The introduction of traditional Chinese mineral medicine

In the above two medicines, there is one kind of mineral medicine–gypsum. The history of Chinese medicine in China is long and profound. Chinese medicinal materials are divided into three categories according to raw materials: Plants, minerals and animals.

Monitoring and preservation of stone cultural heritage using …

Mirabilite, thenardite, gypsum and halite have also been found. Other mineralogical tests have been performed on white powders sampled by efflorescence. XRDs show the presence of salts with ...

[PDF] Gypsum, mirabilite, and thenardite efflorescences of …

The efflorescences are composed of mixed sulfates, including gypsum, mirabilite, and thenardite, whose development depends on the stone–environment interaction. The underground environment is extremely humid and water is the main driving force of salt weathering, having a twofold function.

Precipitation of Laumontite with Quartz, Thenardite, and Gypsum …

X-ray powder diffraction, scanning electron microscope (SEM), and electron microprobe analyses show thenardite to be the dominant phase in the exterior coatings, in association with minor microcrystalline (<50 μ m) laumontite and gypsum. Macrocrystalline (>1 mm) laumontite is the dominant phase in interior fracture coatings and is associated ...

Gypsum, mirabilite, and thenardite efflorescences of tuff …

The development of salt weathering can be discussed in terms of the environmental factors affecting the stability of the mineral phases involved. Gypsum, mirabilite, and thenardite all have their own thermodynamic behavior, so the microclimate and its variability play an extremely …

Thenardite and gypsum precipitated in wall of brick …

Fine-grained white sulphates were precipitated in wall of brick building in the campus of the University of the Ryukyus, Okinawa. The sulphate samples scratched by knife were investigated by X-ray diffraction analysis (XRD), optical microscopy, and scanning electron microscopy (SEM). The precipitated sulphates are thenardite and gypsum. These …

Drying of gypsum plaster prisms: prevention of visible

It is almost purely made of sodium sulfates, primarily thenardite in addition to mirabilite. Gypsum and anhydrite were scratched off from the prism surface as well. The elevated background can be attributed to desiccator grease. To fit the elevation, the background was constrained to 1st Chebichev order before the beginning of the actual ...

Thénardite: Meaning, Properties, and Benefits You Should …

Thenardite crystal's meaning is ... Thénardite-Gypsum: Protective in its grayish-white hue, this crystal shields users from negative influences, promoting a safe and harmonious environment. Thénardite-Inyoite: Exhibiting a warm golden tone, it stimulates creativity and artistic expression, inspiring innovative endeavors.

Validation and Recalibration of the Solubility Models in …

As gypsum/anhydrite in salt formations controls the sulfate concentrations in associated brines, we test the gypsum solubility model in NaCl solutions up to 5.87 mol•kg–1 from 25°C to 50°C. ... The model is much less ideal in reproducing the compositions in equilibrium with the assemblages of halite + thenardite, and of halite ...

[PDF] Gypsum, mirabilite, and thenardite efflorescences of …

The efflorescences are composed of mixed sulfates, including gypsum, mirabilite, and thenardite, whose development depends on the stone–environment …

Minerals in Ohio

Type of mineral occurrence: gypsum crystals, ironstone septaria The Crystal King in Ohio Caverns is one of the largest and most perfectly formed stalactites in the world. It has been in the process of forming …

Precipitation of laumontite with quartz, thenardite, and gypsum …

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Evaporite minerals and geochemistry of the upper 400 m …

The detailed mineralogical investigation focused on evaporite minerals including halite, gypsum, mirabilite, thenardite, glauberite, eugsterite, and bloedite. Gypsum and halite make up the majority of the evaporate minerals. Environmentally induced variations in the mineralogy and crystal habit of the sulfates have been …

Influence of alkali sulfates in clinker on the hydration and …

With the addition of thenardite, 1 d compressive strength of mortars tends to decrease with the increase of alkali sulfate/SO 3 ratio. Thenardite leads to higher 1 d compressive strength than arcanite and aphthitalite when cement has high SO 3 …

Thenardite

Thenardite is a sodium sulfate salt (Na 2 SO 4) usually found together with other sulfate salts such as mirabilite or Glauber's salt (Na 2 SO 4 ·10H 2 O), glauberite (Na 2 Ca(SO 4) 2), bloedite or astrakanite (Na 2 Mg(SO 4) 2 ·4H 2 O), or burkeite (Na 6 (CO 3)(SO 4) 2).. Sodium sulfate deposits can be classified into three main groups: …

Thénardite from Gypsum mine, Wienern, Grundlsee, Liezen …

Gypsum mine, Wienern, Grundlsee, Liezen District, Styria, Austria. Photos Maps Search. Standard. All Photos (9) Specimen Photos (6) Locality Photos (3) Gallery Photo Statistics Add Photo. Map Pages Nearest Localities. Mineral Search Similar Localities Nearest Localities Predictive Mineralogy Search Google. Locality type: Mine: Classification:

Thénardite

Thenardite is colorless when pure, but most often takes on a gray, brownish, reddish, or yellowish tint. It is soluble in water and has a slight saline flavor. ... {110}, frequently forming cruciform groups. A twin is also present on {011} resembling that of gypsum.

Gypsum, mirabilite, and thenardite efflorescences of …

Gypsum, mirabilite, and thenardite eorescences of tu stone in the underground environment Luigi Germinario1,2 · Chiaki T. Oguchi2 Received: 26 September 2021 / Accepted: 11 March 2022

Thénardite

This 2x4x2 inch cluster of thenardite came from the evaporite deposits at Soda Lake about 25 miles west of Taft, California. In the Charles Creekmur collection. ... that was likely worked for salt as long as 2000 years ago (MINDAT). The Camp Verde Mine, a salt-clay-gypsum mine, was active in the 1920s and 1930s. Many fine and unusual specimens ...

Visible to near-infrared reflectance and Raman spectra of …

Despite this, in VNIR spectra, gypsum and thenardite were the identifiable salts for AHSa and gypsum for AHSb. In Raman analysis, gypsum was also identifiable for both samples. Gypsum has been identified in situ on Mars, notably precipitating diagenetically in veins through outcrops (e.g., Nachon et al., 2014). In a system such as …

Sodium sulphate deposits of Neogene age: the Kirmir …

Thenardite facies in the galleries of the Çayirhan mine (A–D), mirabilite texture (E), and secondary gypsum textures (F and G). (A) Thenardite layers. Hammer for scale. (B) Detail of the coarse-grained thenardite texture composing the thenardite layers. White bands in the central part of the picture correspond to secondary mirabilite.

Influence of alkali sulfates in clinker on the hydration and hardening

The XRD patterns of arcanite, thenardite, aphthitalite and Ca-langbeinite are shown in Fig. 1. Arcanite was produced. Reactivity of alkali sulfates. Sulfates, mainly occur as gypsum as well as alkali sulfates, in Portland cement reacts with C 3 A to form ettringite or monosulfate during cement