Why Porcelain Is So Expensive | So Expensive | Business Insider

I'll admit that I do wish today's video would do a little better job of telling what porcelain is rather than just telling why it's so labor intensive to make.

So I went looking around the intertubes to find some definitions of what porcelain is.

From wikipedia...

Porcelain is a ceramic material made by heating raw materials, generally including kaolinite, in a kiln to temperatures between 1,200 and 1,400 °C (2,200 and 2,600 °F). The greater strength and translucence of porcelain, relative to other types of pottery, arise mainly from vitrification and the formation of the mineral mullite within the body at these high temperatures.

From Britannica...

Porcelain, vitrified pottery with a white, fine-grained body that is usually translucent, as distinguished from earthenware, which is porous, opaque, and coarser. The distinction between porcelain and stoneware, the other class of vitrified pottery material, is less clear. In China, porcelain is defined as pottery that is resonant when struck. In the West, it is a material that is translucent when held to the light.

From Webster's...

a hard, fine-grained, sonorous, nonporous, and usually translucent and white ceramic ware that consists essentially of kaolin, quartz, and a feldspathic rock and is fired at a high temperature

From Far and Away...

Ceramic is a broad term for various materials that are made by firing clay or other mixtures at extremely high temperatures. Generally, it includes products such as pottery, tiles, and cookware. The surfaces of ceramic can be painted or glazed to create different finishes and styles.  

Ceramics are usually broken down into three categories: porcelain, stoneware, and earthenware. 

Porcelain is denser than stoneware and earthenware, which makes it the strongest type of ceramic. In addition to its strength and durability, porcelain also has an extremely smooth surface that lends itself well to decorative treatments such as hand painting or airbrushing. Porcelain is also the least porous type of ceramic material, which makes it ideal for use in bathrooms or kitchens where watertightness is important. Earthenware is the softest type of ceramic material and can be very delicate in nature. It also has a tendency to absorb moisture easily. 

Earthenware pieces tend to be thicker than their porcelain counterparts due to their lack of strength and durability. As a result, they are often produced in simpler shapes with fewer decorative details since any intricate detail may be too delicate to survive regular use or exposure over time. 

Stoneware falls somewhere between porcelain and earthenware in terms of strength and durability making it a popular choice for everyday items like plates or mugs since it can withstand some wear-and-tear but isn’t overly fragile like earthenware pieces tend to be. Stoneware has been used throughout history for many types of items including storage jars, jugs, figurines and table services sets due its versatility in design options depending on the levels at which it’s fired during production processes.

...

Porcelain is a fine-grain ceramic material made from kaolin, a white clay mined in various parts of the world. It is used for tableware, tiles, and other applications where strength, hardness and stain resistance are desired. 

Porcelain has an extremely low porosity—it is nearly waterproof—and it is considered to be thermal shock resistant. It can withstand temperatures up to 1800 degrees Fahrenheit and it does not react with chemicals in the same way as other ceramics. Porcelain can accept a wide variety of decorative glazes and finishes, which makes it ideal for many applications. 

When comparing porcelain to its relative ceramic, there are some key differences to consider: 

Porcelain has a finer grain than ceramic and its ingredients go through more processing before they can be used as a material choice. 

Due to its high degree of density, porcelain is more durable than ceramics but it also costs more because of the processing involved in producing the material.

So, there you go...

The Most Reflective Mirror In The World

Arrggghhh, Action Lab again.

I want to hunt down some of those dialectric mirrors. Their non-isotropic reflective materials sound pretty cool.

I am amazed that there is no metal in the material. It's just made of transparent polymer layers in alternating materials with different indices of refraction.

How Does Noise-Cancelling Tape Work?

Argh, Action Lab again.

I don't care for the host as a video host, but I do like some of the experiments he gives and the experiments he shows...sometimes.

This video shows noise-damping tape which incorporates a viscoelastic layer to the tape, causing a significant amount of damping for the vibrations in the cookie sheet that Action Lab uses as a frugal gong.

Best Rust Converter? POR-15, Eastwood, Rust-oleum Rust Reformer, Gempler's

One of my coworkers recommended this video to me, and I respect the video host's adherence to the scientific method. He tests metal from the same source, prepared in the same way, and has multiple test samples for each coating.

I'm not so sure, however, what these rust convertors actually do. I found this in the wikipedia article on rust converters...

Commercial rust converters are water-based and contain two primary active ingredients: tannic acid and an organic polymer. Tannic acid chemically converts the reddish iron oxides into bluish-black ferric tannate, a more stable material. The second active ingredient is an organic solvent such as 2-butoxyethanol (ethylene glycol monobutyl ether, trade name butyl cellosolve) that acts as a wetting agent and provides a protective primer layer in conjunction with an organic polymer emulsion. 

 

Some rust converters may contain additional acids to speed up the chemical reaction by lowering the pH of the solution. A common example is phosphoric acid, which additionally converts some iron oxide into an inert layer of ferric phosphate. Most of the rust converters contain special additives. They support the rust transformation and improve the wetting of the surface.

Looks like they're primarily tannic acid with some organic solvents.

The science seems pretty interesting, and I might show this video to my students when we discuss experimental design methods.

Reusable handwarmers that get hot by freezing

The title of this video is wrong.

There is no freezing happening. There is recrystallization happening from sodium acetate dissolved in solution.

That's not freezing - a pure liquid turning into a solid like ice turning into water. The host seems to understand that distinction, but he's sloppy on using the term freezing and freezing point somewhat misleadingly. He also is sloppy on liquid versus solution and melted versus dissolved.

Most of this video is an explanation and comparison of the two types of hand warmers - the reusable sodium acetate solution and the single-use iron rusting type. The video host explains the science behind what's happening and judges the single-use to be the better choice - something that I'll leave up to you.

I use both in class for different purposes and different chapters.

The Wrong Stuff

Source - xkcd
Rollover joke - The phantom found Edward Everett Hale a century too early; by the time we invented satellites, the specifics of his 'brick moon' proposal were dismissed as science fiction.

See, it's funny because...building a spaceship out of bricks would be an amazingly bad idea. They're not airtight. They're heavy. They're just not what you should build a spaceship out of.

Then again, a wooden airplane built for World War II wasn't necessarily a great idea either.

Nor was a pykrete aircraft carrier.

The Trojan Horse, on the other hand, was clearly a great idea.

Sulfur demo - monoclinc and amorphous

 

Yeah, that's about how we do it in class and in our summer camps.

I'm always on the lookout for decently filmed versions of labs that we do in class so that I can post videos for my students who miss those days.

So I'm happy to have found these videos. Thanks, Bird Among the Trees (?).

I'll post a couple more videos of the same processes but done differently than how we do them in class, but I'll put those after the jump.