earth science

Jargoon

Jargoon 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 Jargoon rather than just read about it. In short: Jargoon or jargon (occasionally in old writings jargounce and jacounce) is a name applied by gemologists to zircons that are of sufficient quality to be cut as gemstones, but not the red color that characterizes the hyacinth or jacinth. The word is related to Persian zargun (zircon; zar-gun, "gold-like" or "as gold").

Key takeaways

Jargoon 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 Jargoon to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Jargoon from memory before moving on to harder problems.

Reference excerpt

Jargoon or jargon (occasionally in old writings jargounce and jacounce) is a name applied by gemologists to zircons that are of sufficient quality to be cut as gemstones, but not the red color that characterizes the hyacinth or jacinth. The word is related to Persian zargun (zircon; zar-gun, "gold-like" or "as gold"). Some of the finest jargoons are green, others brown and yellow, while some are colorless. The colorless jargoon may be obtained by heating certain colored stones. When zircon is heated it sometimes changes color, or loses it, and at the same time usually increases in density and brilliancy. The so-called Matura diamonds, formerly sent from Matara (or Matura) in Sri Lanka, were decolorized zircons. The zircon has strong refractive power, and its lustre approaches adamantine, but it lacks the fire of diamond. The specific gravity of zircon is subject to variation in different varieties; thus Sir A. H. Church found the specific gravity of a fine leaf-green jargoon to be as low as 3.982, and that of a pure white jargoon as high as 4.705. Jargoon and tourmaline, when cut as gems, are sometimes mistaken for each other, but the specific gravity is distinctive, since tourmaline is only 3.103. Moreover, in tourmaline the dichroism is strongly marked, whereas in jargoon it is feeble. The refractive indices of jargoon are much higher than those of tourmaline.

References

Sources Kunz: Gems and Precious stones of North America; Zircon

External links Media related to Jargoon at Wikimedia Commons

Illustrations

Worked examples

Example 1 — a first encounter with Jargoon

Start with the simplest possible case. Write down what Jargoon 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 Jargoon 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 Jargoon 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 Jargoon

In research: Jargoon 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 Jargoon 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: Jargoon is common in secondary-school and first-year university syllabi. It links to neighbouring topics Gemstones, Mineralogy stubs, Petrology stubs, so understanding it makes those chapters shorter.
In everyday life: Look for Jargoon 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 Jargoon in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Jargoon 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 Jargoon out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Jargoon in simple terms?

Why does Jargoon 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 Jargoon?

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 Jargoon.