Monday, September 1, 2014

Birthstones: Opal (October)

October's child is born for woe,
And life's vicissitudes must know,
But lay an opal on her breast,
And hope will lull those woes to rest.

 Opal is a really fascinating gemstone, both in appearance, composition, and history. You can tell right away by the brilliant play of color that is the trademark of (one of) October's birthstones:

One reason that opal is particularly interesting is that is the first birthstone in this series to not be a proper mineral.

A mineral has a uniform, organized structure throughout the entire specimen. One bit of a mineral looks largely like the next. Quartz is Si04 all the way through, ruby and sapphire are Al203 all the way through, and so on.

Opal is classed as a mineraloid—as being almost a mineral. It does have bits and pieces of regularity, but they are not found overall. Instead, an opal's crystal structure (such as it is) is akin to marbles in a vase: globs of order and structure (silicates) with bits of empty space in between. As it is hydrated, some of those gaps in between the marbles are filled with water. From 6%–10% of a given opal's weight may consist of water, though it can be as low as 3% and as high as 21%.

It is the space between that is the opal's favorite Dave Matthews Band song creates the brilliant play of color so renowned in opal. That space distorts and bends the light, resulting in a variety of different colors. You can think of an opal as an aggregate of lots of little prisms.

Microscopic silcate beads in opal.

The name "opal" likely can be traced to the Sanskrit word upala, meaning "precious stone." It comes to us today from Sanskrit to Greek (opallios, now meaning "color change") to Latin (opalus) to Middle French (opalle) to English. Because of the multitude of colors found in it, opals were thought to be comprised of many other precious gems, as Pliny the Elder wrote:

Made up of the glories of the most precious gems, to describe them is a matter of inexpressible difficulty. For there is amongst them the gentler fire of the ruby, there is the rich purple of the amethyst, there is the sea-green of the emerald, and all shining together in an indescribable union.

Opal was a popular stone among blondes, as it was thought to be a remedy against darkening hair. It was an opal ring that granted invisibility in the tale of Gyges, and thereafter in Western thought it was associated with invisibility.

Something like 97% of the world's opal supply comes from Australia, and the stone has long been treasured by Aboriginals. They associated the stone's rainbow flashes with their creator god (who originally came to Earth on a rainbow) and outcrops with opal became sacred ceremonial grounds. However, those were not the opals that Pliny the Elder was writing about; early sources in Europe often came from what is today Hungary, and then from Central America once the Age of Exploration was well underway. The world's earliest opal artifacts (dating to 4000 BCE), meanwhile, were found in Kenya, with opal from Ethiopia.

For a short while, opals were considered an unlucky stone, thanks in large part to Sir Walter Scott's 1827 novel, Anne of Geuerstein. One of the main characters, Lady Hermione, wore a beautiful opal in her hair whose color change matched her mood. After meeting some holy water, both Lady Hermione and the stone became nothing but ash.

This image lodged itself in the popular consciousness and the market for opals plummeted. This decline wasn't helped by the fact that people at the time had no idea how to properly care for opals; more than other precious stones, opal was prone to cracking and breaking, always interpreted as an ill omen.

But opal's beauty is hard to resist. With the discovery of beautiful black opals in Australia in 1877, the market revived. Shortly thereafter, Australia overtook Hungary and other European suppliers as the world leader in opal production.

I'm writing about opal in a general sense, but there are many different types of opal. There isn't any particularly type of opal that is specifically the birthstone and there isn't too much difference between types beyond coloration.

There is white opal, the most common kind of opal. At a distance, it looks more or less white (except for any color play). White opal accounts for about 60% of the world supply of opal.

There is black opal, which looks much darker at a distance. The play of color on black opal is saturated and striking.

A type very similar to black opal is boulder opal. It gets its name from the ironstone boulders it forms on, and is only found in Queensland, Australia. Boulder opal on its own is quite thin, so it's always cut with a bit of the ironstone boulder left on the back; often there is also ironstone matrix throughout the whole cut stone.

If any of the first two types of opal have unusually transparent bodies, they are referred to as crystal opals.

Outside of Australia, the Mexican fire opal has become popular. Its play of color isn't as dramatic as specimens from Australia, but the colors are often fiery reds, oranges, and yellows (hence the "fire" appellation).

Any kind of opal whose play of color is more subdued and less brilliant than average is referred to as a jelly opal. An opal without any play of color at all is called common, or potch opal. Potch opal comprises 95% of the opal mined, worldwide.

Another cool thing about opal is that it is often a replacement medium for fossils. You often find opal in petrified wood (which is to say, you often find opalized wood) and other fossilized things, including ammonites.

For some reason I never knew this until a few months ago. You learn something new every day, or something.

Because the most beautiful opals command high prices, there are of course different methods of synthesizing or imitating opal, or just reducing the cost.

If you delve at all into the online opal mines you will find people discussing doublet and triplet opals. These are slim pieces of opal epoxy'd on to a backing: sometimes potch opal, sometimes another darker, sturdy stone, sometimes black glass. This is a doublet (as in two layers, or double). A triplet is a doublet with a dome of quartz affixed to the other side of the opal—3 layers. This has long been a common way for people to create affordable, opal-like jewelry.

Opal has been synthesized since 1974, and the practice continues today, Lab-grown opals can be distinguished from natural ones by their play of color (it is much more regular and symmetrical, with larger color bands, in lab-grown than in nature). Natural opals also fluoresce, while lab-grown ones do not.

 Many, though not all, synthetic opals are more properly called imitation, as they contain ingredients not found in natural opals (plastic stabilizers, primarily). An even lower-budget imitation opal is just colored foil under glass. This was a popular choice for costume jewelry, especially during the Art Nouveau movement.

Opals also require some more care and attention than other birthstones. They benefit from lots of contact with skin, as they are hydrated mineraloids; without periodic exposure to moisture, they tend to become brittle and crack easily. They are also sensitive to sudden changes in temperature or humidity. Solid opals are not damaged by being submerged in water, but this should be avoided with doublets and triplets.

There are some misnomers out there in the world. "Opalite," for example, is not opal but is a glass imitation with similar play of color. "Sea opal" is merely sea glass. "Slocum opal" another glass imitation opal, though it less popular these days than opalite. They are all quite lovely, but intentionally marketing them as genuine opals is a pretty crappy thing to do.

Saturday, August 30, 2014

Friday Find: Scientifiques

The Etsy circle feature has been more of a bane than a boon for me. No matter how many times I clear out my "following" list, 90% of what shows up in my feed is just Not For Me.

That other 10%, though, includes some real gems, like Scientifiques. Everything Lorraine has is gorgeous and handcrafted, and she is obviously inspired by a variety of STEM fields! From math:

Euler's identity math bracelet jewelry from scientifiques.
Euler's identity cuff bracelet by scientifiques

to paleontology:

Green River bat fossil photo pendant by scientifiques
to chemistry:

Carbon science jewelry scientific necklace by scientifiques.
Etched Copper Carbon Period Table Pendant by scientifiques

In particular I love her use of metal (a skill I wish I had but at the moment don't have the supplies or space for). I love the warm brown of copper and am glad to see someone using it in the jewelry world. And check out this piece de resistance:

Diplocaulus Fossil Skull Necklace by scientifiques
Talk about a statement piece!

Thursday, August 28, 2014

Trek Thursday: Court Martial

#65: Court Martial

In case you forgot: Kirk is on trial for the death of one of his crewmen owing to gross negligence (Starfleet suddenly cares about all those redshirts now?). THE COMPUTER has damning evidence against him, but the man Kirk stands accused of killing is still alive and has tampered with the memory banks in attempt to destroy Kirk's career and exact his revenge.

This week, on Perry Mason in Space...

That's all this episode is, really, and if you like procedurals then this episode gets a lot better. If you don't, though, you're SOL. The dated worries over man versus machines might have struck a chord with contemporary audiences, but it's not a theme that ages well.

Wednesday, August 27, 2014

What I'm Playing: HabitRPG

You're all playing HabitRPG right now, too. You just don't know it yet.

See, someone finally had the idea to gamify real life and give you rewards like gold and XP for completing arduous tasks like doing the dishes, exercising, or cleaning your apartment. Brilliant!

I'm only level 3 right now, so there isn't a whole lot of world content available for me at the moment. I'm sure that'll change soon: I am constantly adding new tasks to accomplish (like writing blogposts) and leveling up like crazy.

The best part about HabitRPG is that it is absolutely free. There's not much in the game you can't purchase or acquire for free, though you can unlock some things faster by donating to the site. I've only been using it for a couple days but already I'm more motivated to stay focused on tasks and get important things done. Which is sad, I guess, but that's how it goes: sometimes you need some external motivation to get things done!

Monday, August 25, 2014

Birthstones: Sapphire (September)

A maiden born when September leaves
Are rustling in September's breeze,
A sapphire on her brow should bind
`Twill cure diseases of the mind. 

After our brief trip back into silicates with peridot, in September we're returning to corundum. Instead of silicon and oxygen, it's composed of aluminum and oxygen.

Then what's the difference between a ruby and a sapphire? What makes them different colors? Chemical impurities. Ruby contains trace amounts of chromium; sapphire contains iron and/or titanium.

("But doesn't iron make things orange-y?" In silicates, yes. Not in oxides. This is the same reason why chromium makes silicates look green, but ruby red. It forms different kinds of bonds that reflect or absorb light differently.)

A cool effect you can get both in rubies and in sapphires is a "star": a rutile (titanium dioxide) crystal forms within the gem and creates a 6-lined star shape. This affect is called "asterism." It's fairly rare in nature, but it's possible to induce this effect in lab-grown sapphire.

Star sapphire is formed by rutlite crystals within the sapphire.
The name sapphire has a complicated history. The origins of its name can be traced conclusively to the Hebrew sappir, but it is likely even older than that. That became the Greek sapheiros, which was simply "blue stone." Such a precise name meant that many ancient blue stones were also called sapphire. Lapis lazuli, for example, was often referred to as sapphire, while sapphire might have been called hyakinthos by the ancient Greeks. There is another school of thought that suggests the name comes from Sanskrit sanipriya ("precious to Saturn"). It's difficult to say when, precisely, the name sapphire was pinned down to Al2O3.

Of course, as we learned with rubies, sapphires can come in a variety of colors besides blue.

Sapphire can also be found in shades of green.

Sapphire can also be found in shades of yellow.

However, it's the blue sapphire that is most often associated with September and has the most lore associated with it. Al203 in other colors were most likely confused for other stones, or considered separate.

Sapphire is a stone that has been around for a long, long time, as evident by the age of the name, so of course it's picked up a fair amount of folk beliefs and traditions!

Ancient Vedic astrologers believed the stone magnified the positive qualities of Saturn (otherwise considered an unlucky planet): leadership, ambition, responsibility, patience, and longevity. Clergy in the Middle Ages often wore sapphires (or other blue gems) to represent heaven, perhaps creating or just only reinforcing the belief that the stone attracted heavenly blessings. Royalty wore it as a charm against envy. Renaissance thinkers held that the stone could cure anger and stupidity.

The first sapphires were probably sifted out of alluvial (riverbed) deposits, where they are still found today (in addition to underground mines). The largest sapphire producers in the world are Madagascar and Australia. Some of the finest and most famous stones, however, have been mined in Sri Lanka.

Sapphire has also been synthesized since the early 1900s. The process leads to a proper, chemically-identical synthetic stone. Fortunate, because sapphire also has a lot of practical applications; particularly, it can be used for a special kind of glass that can tolerate a heavy heat load and also "let through" a broad spectrum of light. It also is scratch-resistant (considering the only thing harder than it is diamond) and extremely durable. "Sapphire glass" is used in lasers, spectrometers, barcode scanners, those xenon headlights everyone hates so much, and for shatter-resistant windows in armored vehicles. You can also find sapphire in cellphones, emergency vehicle radios, and satellite communications systems. It's quite the multipurpose stone!

Note that there, as always, unscrupulous people intent on trading on the prestige of sapphire's name. I've seen items on Etsy that list "sapphire jasper" as one of their materials used, but that's just a trade name. It's more likely variscite (also known as aqua terra jasper, snakeskin jasper, or impression jasper), which is a beautiful stone....but not actually sapphire. They are related only in that they are pretty.

Natural sapphires are often treated to improve their color and clarity; there are ones that are naturally brilliant and saturated with color, but they are rare and fetch a high price. There are, yes, synthetic ones as well, but beware artificial sapphire (usually just colored glass) posing as the real thing.

Friday, August 22, 2014

Read Play Blog

I stumbled across this from Karsyn! Read Play Blog is a monthly gaming-related meme hosted by Read Me Away and Happy Indulgence Books that goes up on the 16th of every month. This has just gotten underway, so there are only two sets of questions so far; like Karsyn I'm going to answer those now and then the following months I'll answer on the 16th like everyone else.



How did you get into gaming?

Lawyer Mom went right back to work after having me and my brother. Dad worked, too, so they hired a full-time sitter for us: a woman whose son became like our favorite cousin. He was some years older than us and very into video games; I remember playing (or more, watching him play) Legend of Zelda on the NES and going head-to-head in the versus mode of Sonic 2. He also had a GameGear and a Gameboy (there was no Nintendo v. SEGA rivalry in that house, believe it or not!) that he trusted us to play with when he was at school.

My brother and I both became hooked. From the SNES on, we had a console of our own we could play at home. SNES to Dreamcast to GameCube to Wii; now I live with JV who owns a GameCube, a PS2, a PS3, an XBox 360, and a Retron console that plays Genesis (sorry, I'm in Europe: Megadrive), NES, and SNES cartridges. He also has a Dreamcast tucked away somewhere.

What do you recommend for new gamers?

It depends so much on what you have and what you like. I think Minecraft is a nice introduction to gaming, because you can do whatever you want and make it as easy or as hard as you want. I think platformers are good, too. They're easy to get the hang of, even if they're fiendishly difficult, and I think that's what most people think of when they think "video game." Little Big Planet is a lot of fun, and it has a good coop mode so if you're not very good, you can get someone else to play with you and help you out.

I recommend you ask a friend who likes games (and you!) to make recommendations, or to ask if you can join them (if possible) on a game or two so you can try it out yourself with a friendly hand to guide you.

What game you are currently playing?

I've finished the main storyline of Ni no Kuni and have moved on to the "postgame" content. I say "postgame" because I still haven't beaten the final, FINAL boss. Lately, though, I've been playing the PS3 version of Minecraft with JV. When I have nothing else I feel like playing, I pop in Fallout 3 and run a few side quests here and there. I finished the main storyline in that, as well, or most of it (not the storyline in the DLC; I think I have a few quests left in that). There is just so much to do in that game, I don't think I'll ever finish it.

Theoretically I'm also playing Demon's Souls, but if I'm to be honest, most of my gaming time is taken up with Ni no Kuni and Minecraft.

JV also just bought Diablo III, a game I've been looking forward to for FOREVER, but I'm hesitant to get started with it now because I know I will be addicted by the time I clear the first dungeon.

What is your favorite gaming genre?

I will play most anything, truth be told. The easier question is, what is your least favorite gaming genre?, and that is FPS. I don't like the mechanics of the FPS most of the time (at least Fallout 3 gives you the VATS aiming system!) and I don't like the "gritty war shooter simulator" genre of Call of Duty (or as we call it, CALLERDERTY) or Wolfenstein or Battlefield or so on. It seems like a lot of bullshit macho posturing.

Anything else is fair game. I enjoy mellow puzzlers (Karsyn mentioned MYST in hers, and that game was my childhood), I enjoy platformers, I enjoy puzzle/adventure RPGS (Zelda, Ookami, etc.), I enjoy RPGs and JRPGs....anything, really.

Thursday, August 21, 2014

Trek Thursday: Tomorrow is Yesterday

#66: Tomorrow is Yesterday

In case you forgot: The Enterprise accidentally travels through time  to late 1960s Earth and works desperately to undo the impression they fear leaving.

When you're dealing with science fiction, time travel is going to be a tempting (if not downright inevitable) plot point that comes up. This is the first such instance in Star Trek (discounting the last, weird ten minutes of "The Naked Time") and it was just as irritating upon rewatching as it was the first time I saw it. How could Spock (or the computer) fail to realize that captain Christopher would end up fathering the captain of the first successful Earth-to-Saturn probe? That seems like a pretty obvious oversight.

Shouldn't their encounter with a black hole-style anomaly have propelled them into the future, not the past? On the flip side of that coin, why does their "slingshot around the sun" idea send them forward in time instead of further into the past? If they've already messed with the timeline by taking Christopher aboard, how can they trust any of the history in the ship's databanks? More importantly, why does the Enterprise and everyone on it still exist? What if the Enterprise's visit to Earth is supposed to be part of the timeline? (And why doesn't Spock consider that last point?)

The logical consistency in this episode is just a big pile of NOPE.

The one redeeming factor is a little touch of melancholy at the end. It was Christopher's dream to go into space, and he got to do it, but he won't ever remember that he did. Kirk's runaround with the security is also pretty entertaining.