Growing Opals In The Lab

Opals are unique amongst gemstones, being formed from tiny silica nanospheres arranged in precise structures that give them their characteristic shifting color when seen from different angles. [The Thought Emporium] loves a challenge, so set about growing some himself.

It’s not the hardest gemstone synthesis ever, but it’s no cakewalk either. The process requires tetraethyl orthosilicate, or TEOS, which can be difficult to find, but the rest of the chemicals required are commonly available. The initial phase involves mixing the TEOS with reactants to form nanoscale silica spheres in the range of 200-350 nanometers wide. With the spheres in solution, the mixture must then be carefully dried in such a way as to create the right structure to produce opal’s famous color effects. At this stage, industrial producers add further silica to stabilize the matrix, though [The Thought Emporium] wasn’t able to find literature that explained how to do this. Instead, he relied on resin, which while imperfect, did allow the specimens to be stabilised and shown off for the purposes of the video.

The video notes that many of the steps in this process were perfected decades ago, but remain held as trade secrets, making replication an exercise in experimentation. Nonetheless, success was had in producing recognisably opalescent specimens, and we can’t wait to see further refinement of the DIY process.

We’ve seen similar work from [The Thought Emporium] before, exploring structural color and holograms. Video after the break.

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DEF CON 27: The Badge Talk; Or That One Time Joe Grand Sourced 30,000 Gemstones

Yesterday we published a first look at the hardware found on the DEF CON 27 badge. Sporting a magnetically coupled wireless communications scheme rather than an RF-based one, and an interesting way to attach the lanyard both caught my attention right away. But the gemstone faceplate and LED diffuser has its own incredible backstory you don’t want to miss.

This morning Joe Grand — badge maker for this year and many of the glory years of hardware badges up through DC18 — took the stage to share his story of conceptualizing, prototyping, and shepherding the manufacturing process for 28,500 badges. Imagine the pressure of delivering a delightful concept, on-time, and on budget… well, almost on budget. During the talk he spilled the beans on the quartz crystal hanging off the front side of every PCB.

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Hackaday Links: April 11, 2012

This hurts our head

You know you can ‘freeze’ drops of water in mid-air by flashing a LED at the right time, right? Well, according to this video you don’t even need a strobing light; just use the frame rate of the camera. Much cooler if you don’t know how it works, in our humble opinion.

Now do Junkyard Wars!

[James Cameron] and [Mark Burnett] (the guy who created Survivor) are bringing Battlebots back to the Discovery Channel. The new show is called Robogeddon and calls upon the current talent in the fighting robot world. Our prediction? Someone is going to build an amazing piece of art that will be completely destroyed in the first round; a wedge with wheels will take the championship.

A steam engine made out of rocks

[Hansmeevis] just spent 230 hours hand carving a steam engine out of gems. It’s called “Dragon’s Breath” and it’s an amazing piece of work: the cylinder is carved out of quartz, while the flywheel, mount, and base are carved out of jasper, onyx, zugalite, and other semi precious gems. Amazing artistry and it works.

Don’t lose a finger on all that science over there

[Dr. W] is a science teacher in Saint-Louis, France. Next year, his students will be learning about reaction propulsion and impulse conservation. To demonstrate these properties, [Dr. W] hacked up an old vacuum cleaner in to a jet engine and built a Pitot tube to measure the 140 km/h wind speed. Google translation.

Circuit bending a Sega Saturn

Making cool glitched-up graphics from Ataris and Nintendos is old hat, but not much has been done with circuit bending slightly more modern consoles. [big pauper] found his old Sega Saturn in his grandma’s attic and wondered what secrets this forgotten box held. It turns out he can make some pretty cool sounds and even cooler glitched out graphics. The pic above is from Virtua Fighter; done correctly these glitched low-polygon graphics could easily find themselves in a very stylistic indie game.