Obsidian- it's the new PMV-11

[Malcolm Schweizer]

Move over PM-V11, and move over microns as well. Obsidian will be the new blade of choice, and angstroms the new measurement of sharpness. 0.5 microns? That's so dull. That's 5,000 angstroms. I can get down to 30 angstroms with obsidian. That would be 0.003 microns.

http://edition.cnn.com/2015/04/02/health/surgery-scalpels-obsidian/index.html

...and guess what- it's actually old-school technology.

[Matthew N. Masail]

Fun read, Thanks. I wonder which "household razors are 0.03-0.06 microns... " unless the math is wrong and it's 0.3-0.6.

[george wilson]

Not really new news. Obsidian fractures into cutting edges one molecule thick. Very brittle,as the article said,and dangerous to use because of that. Jewish mohels have used stone cutting tools since ancient times for circumcision.

Researchers have found obsidian to be extremely effective in experimentally cutting up road kill deer carcasses like ancient man did his hunted quarry.

[Daniel Rode]

I want to eventually learn to chip my obsidian freehand (free-chipping) but for now I use an old Neanderthal chipping jig I bought on ebay. A deer antler and flint guide will only get down to 3 molecules thick, but I strop on limestone and that seems to make the edge less brittle. I've been researching leather lap covers for free-chipping, but mammoth leather is getting scarce.

[Daniel Rode]

http://wildwoodsurvival.com/survival/flintknapping/trm/trm1-4pg17.html

[steven c newman]

Be very careful. Aztecs used to inbed big chunks in a war club, and take an arm, leg or head OFF with a swing.

[Mel Fulks]

Saw a news paper story some years back about a modern surgeon using an obsidian scalpel. Don't think that was his
routine,think it was a special case to limit scarring.

[Noah Wagener]

Daniel, the Natives would bake their stones before shaping their arrowheads and knives. It actually made them more brittle though which is what they wanted for flaking. I do not know why they would need something so sharp as i have never seen a Native that needed a shave. Come to think of it, i've never seen a bald one either. Must be some hormonal thing.

[Kent A Bathurst]

Most important use of all - it is the only substance that can kill the White Walkers that live north of The Wall. If they ever get south of the Wall, all of Westeros is gonna want to have some on hand.

[Malcolm Schweizer]

Just before anyone gets too serious, I don't really expect it to work for plane blades, but this might make for a good April Fool's next year for Veritas to offer Obsidian blades. (Can't really call them "irons" anymore.) The article, however, is very interesting. They are using it for scalpel blades for microsurgery.

[george wilson]

At least some indians had their facial whiskers killed off as babies: Their mothers held their faces over scalding hot steam coming from water poured over very hot rocks,destroying the follicules (sp?).

Other times,they used a pair still connected clam shells as tweezers.

[Jim Davis]

Would like to read support for the scalding of follicles. Also, chert and flint were baked, but not obsidian.

[Kent A Bathurst]

Would like to read support for the scalding of follicles. Also, chert and flint were baked, but not obsidian.

George is speaking from personal observation. He was there at that time. :p

[Jim Matthews]

That's another episode of Dallas I missed.

[Ryan Mooney]

Never made anything from obsidian, but I have made some stuff from sevenupite which reportedly behaves somewhat similar (they're both a glass anyway so moreso than flint or chert). If nothing else it yielded vast respect for the folks who can consistently produce a nice blade from this sort of thing.

[Tom Vanzant]

At least sevenupite is a more attractive color than coorsite, although they're about equal in cutting.

[Shawn Pixley]

Very old school. We used glass blades for microtome sectioning. I used obsidian for human sacrifice. But now my duities are largely ceremonial.

[steven c newman]

Used to use( and still do) pieces of broken window glass as scapers. Easy to sharpen, just cut a new edge. Have a contour to scrape? Make the cut in the glass match it. Will scrape on either the push, or the pull stroke. You can always get scraps from a local glass installer. Sometimes, they are even free.

Black Glass? IF there was any around here, I would try that, too.

[Darren Brewster]

Most important use of all - it is the only substance that can kill the White Walkers that live north of The Wall. If they ever get south of the Wall, all of Westeros is gonna want to have some on hand.

Winter is coming.

[george wilson]

When I was student teaching shop,the shop teacher had taught his students to use broken glass as scrapers. I was shocked to see them using unevenly broken glass to try scraping flat wood. They just cut grooves in the wood,totally ruining it.

It was not my place at that time to get them to stop doing that,unfortunately. I hope that some day they realized how they were just ruining their work.

You can use broken glass to scrape round work,where there is a single point of contact between the scraper and the wood. But,I prefer to use steel,as it is just safer and will not suddenly break in your hands. I don't want microscopic shards of shattered glass getting into my skin,either.