Stonesetting

Key takeaways

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

Reference excerpt

Stonesetting is the art of securely setting or attaching gemstones into jewelry.

Cuts

There are two general types of gemstone cutting: cabochon and facet. Cabochons are smooth, often domed, with flat backs. Agates and turquoise are usually cut this way, but precious stones such as rubies, emeralds and sapphires may also be. Many stones like star sapphires and moonstones must be cut this way in order to properly display their unusual appearance. A faceted shape resembles that of the modern diamond. It has a flat, polished surface, typically with a transparent surface that refracts light inside the gemstone and reflects light on the outside. In the case of a cabochon stone, the side of the stone is usually cut at a shallow angle, so that when the bezel is pushed over the stone, the angle permits it to hold the stone tightly in place. In the case of faceted stones, a shallow groove is cut into the side of the bezel into which the girdle of the stone is placed, with metal prongs then pushed over the face of the stone, holding it in place; cabochons may also be set into prong settings. In both cases, the pressure and the angle of the prongs holds the stone in place. Just as the angle of the sides of a cabochon creates the pressure to hold the stone in place, so there is an overlying principle in setting faceted stones. If one looks at a side view of a round diamond, for example, one will see that there is an outer edge, called the girdle, and the top angles up from there, and the bottom angles down from there. Faceted stones are set by "pinching" that angle with metal. All of the styles of faceted stone setting use this concept in one way or another.

Settings There are thousands of variations of setting styles, but there are several fundamental types:

Bezel

The earliest known technique of attaching stones to jewelry was bezel setting. A bezel is a strip of metal bent into the shape and size of the stone and then soldered to the piece of jewelry. The stone is then inserted into the bezel, and the metal edge of the bezel pressed over the edge of the stone, holding it in place. This method works well for either cabochons or faceted stones.

Prong

A prong setting is the simplest and most common type of setting, largely because it uses the least amount of metal to hold the stone in place, displaying most of the stone and forming a secure setting. Generally, a prong setting is formed of a number of short, thin strips of metal, called prongs, which are arranged in a shape and size to hold the given stone, and are fixed at the base. Then a burr of the proper size is used to cut what is known as a "bearing", which is a notch that corresponds to the angles of the stone. The burr most often used is called a "hart bur", and is angled and sized for the job of setting diamonds. The bearing is cut equally into all of the prongs and at the same height above the base. The stone is then inserted, and pliers or a pusher are used to bend the prongs gently over the crown of the stone, with the tops of the prongs are clipped off with snips, filed to an even height above the stone, and finished. Usually a "cup burr" is used to give the prong a nice round tip. A cup burr is in the shape of a hemisphere with teeth on the inside, for making rounded tips on wires and prongs. There are many variations of prong settings including just two prongs, the more common four prong setting or up to 24 or more, with many variations involving decoration, size and shapes of the prongs themselves, and how they are fixed or used in jewelry. The method of setting is generally the same for all, no matter how many prongs are present.

Channel

A channel setting is a method whereby stones are suspended between two bars or strips of metal, called channels. Typically, a line of small stones set between two bars is called a channel setting, and a design where the bars cross the stones is called a bar set. The channel is a variation of a "U" shape, with two sides and a bottom. The sides are made slightly narrower than the width of the stone or stones to be set, and then, using the same burs as in prong setting, a small notch, called a bearing, is cut into each wall. The stone is put in place in those notches, and the metal on top is pushed down, tightening the stone in place. The proper way to set a channel is to cut a notch for each stone, but for cheaper production work sometimes a groove is cut along each channel. Since the metal can be very stiff and strong, a reciprocating hammer, similar to a jackhammer but jewelry sized, may be used to hammer down the metal, as it can be difficult to do by hand. The metal is then filed down and finished, and the inner edge near the stones cleaned up and straightened as necessary. As with all jewelry, there can be many variations of channel work. At times the walls will be raised—sometimes a center stone will be set between two bars that rise high from the base ring—or the channel may be cut directly into the surface, making the stones flush with the metal.

Bead

… excerpt ends here. Continue reading the full article.

Illustrations

Stonesetting: Prong set diamonds — Prong set diamonds

Worked examples

Example 1 — a first encounter with Stonesetting

Start with the simplest possible case. Write down what Stonesetting claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In 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 Stonesetting 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 Stonesetting 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 Stonesetting

In research: Stonesetting appears in 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 Stonesetting 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: Stonesetting is common in secondary-school and first-year university syllabi. It links to neighbouring topics Gemstones, Jewellery making, so understanding it makes those chapters shorter.
In everyday life: Look for Stonesetting 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.

How to study Stonesetting in 20 minutes

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

Frequently asked questions

What is Stonesetting in simple terms?

Stonesetting is the art of securely setting or attaching gemstones into jewelry. Cuts There are two general types of gemstone cutting: cabochon and facet.

Why does Stonesetting matter?

Because it connects several 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 Stonesetting?

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 Stonesetting.