earth science

Mosesite

Mosesite is a earth science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Mosesite rather than just read about it. In short: Mosesite is a very rare mineral found in few locations. It is a mercury mineral found as an accessory in deposits of mercury, often in conjunction with limestone.

Key takeaways

Mosesite belongs to earth science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Mosesite to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Mosesite from memory before moving on to harder problems.

Reference excerpt

Mosesite is a very rare mineral found in few locations. It is a mercury mineral found as an accessory in deposits of mercury, often in conjunction with limestone. It is known to be found in the U.S. states of Texas and Nevada, and the Mexican states of Guerrero and Querétaro. It was named after Professor Alfred J. Moses (1859–1920) for his contributions to the field of mineralogy in discovering several minerals found alongside mosesite. The mineral itself is various shades of yellow and a high occurrence of spinel twinning. It becomes isotropic when heated to 186 °C (367 °F).

Composition Mosesite contains 16 Hg, 3 Cl, 1+1⁄2 SO4, 1⁄2 CO3, 1⁄2 MoO4, 16 H, and 8 N with a volume of 0.84777 nm3 and calculated density of 7.53 g/cm3. Its chemical formula is Hg2N(Cl,SO4,MoO4,CO3)·H2O.

Geologic occurrence Discovered in a mercury mine in Terlingua, Texas, mosesite has also been seen in Nevada and Mexico. Mosesite is a secondary mineral formed at low temperature in hydrothermal mercury deposits. The mercury ore at the mine in Huahuaxtla is aligned with ribs of brecciated limestone that formed along a shallow-angle fault plane. In the Huahuaxtla mine, this is due to the evidence of oxidized minerals. The portion of the mine in which the mosesite was found is thought to be a solution cavity in a zone of fractured limestone. Mosesite is never found in abundance in any of the known locations of its origin. Mineral associations include montroydite, calcite, gypsum, and at some localities native mercury.

Structure Spinel twinning is a common occurrence in mosesite. Mosesite was found to have a unit cell with diamond type space lattice and the measured unit cube of Mosesite was approximately 0.944 nm with additional forms {001}, {011}, {116}, {114}, and {112}. In Mexico, the mosesite was most usually found as octahedral crystals which were usually intergrown. Single crystals are rare. Mosesite has a similar structure to Millon’s base (Hg2NOH•nH20). Mosesite consists of a three-dimensional framework of Hg2N+ groups. The mercury atoms form linear sp bonds, while the nitrogen forms tetrahedral sp3 bonds, in a face-centered cubic lattice. The space group of mosesite is F*43m.

Physical properties Mosesite is a minute yellow crystal with imperfect cleavage along {111} and uneven fracture. It is brittle with a hardness of 3.5. Long exposure, a month or more, to light will change Mosesite to a light olive green color. The powdered form retains its color streaking a light yellow. The mineral exhibits no pleochroism and displays uneven birefringence in polarized light. Heat has a notable effect on Mosesite for when heated above 186 °C (367 °F) the mineral becomes isotropic. This corresponds optically with the observed crystal form only at this higher temperature. It is considered weakly anisotropic. The index of refraction is n = 2.065±0.01. It has an adamantine luster that officially ranges in color from lemon yellow to canary yellow. Mosesite reacts chemically with HCl leaving a residue of HgCl.

References

Bibliography Palache, P.; Berman H.; Frondel, C. (1960). "Dana's System of Mineralogy, Volume II: Halides, Nitrates, Borates, Carbonates, Sulfates, Phosphates, Arsenates, Tungstates, Molybdates, Etc. (Seventh Edition)" John Wiley and Sons, Inc., New York, pp. 89-90.

Worked examples

Example 1 — a first encounter with Mosesite

Start with the simplest possible case. Write down what Mosesite claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In earth science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Mosesite before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Mosesite ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Mosesite

In research: Mosesite appears in earth science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Mosesite in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Mosesite is common in secondary-school and first-year university syllabi. It links to neighbouring topics Cubic minerals, Mercury minerals, Minerals in space group 216, so understanding it makes those chapters shorter.
In everyday life: Look for Mosesite outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study Mosesite in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Mosesite means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Mosesite out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Mosesite in simple terms?

Mosesite is a very rare mineral found in few locations. It is a mercury mineral found as an accessory in deposits of mercury, often in conjunction with limestone.

Why does Mosesite matter?

Because it connects several earth science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Mosesite?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Mosesite.