Question for glass blowers. Difference between obsidian and normal glass

Hi there..random question.

Obsidian is a type of glass, apparently the high quality stuff it is mainly silicon dioxide, same as regular glass. Would it therefore be possible to create obsidian instead of glass, simply by adding different impurities?

The melting point might be a factor...different impurities = different mechanical/chemical behaviour I guess, same as steel? Maybe it would be too high?

Or is it the fast cooling that would be difficult to replicate in a glass factory?

The glass has to be cooled slowly and evenly to not crack. And the 33 Coe doesn't mix with any others. If you can get me a tube of obsidian I'll try

It would be interesting...I'm all out of obsidian at the moment I'm afraid....though apparently melting a block of granite into some pure silica would give approximately the right ingredients. Melting granite is extremely easy of course I'm sure! ha

I'm not sure how obsidian manages to cool quickly in nature and not crack from internal stress. Maybe that's just something that needs very special conditions to happen, which could be a problem in a glass kiln too I guess.

I have a black color called obsidian. What bennifits would you get? Is it strong?

So it's cooled lava??? http://en.wikipedia.org/wiki/Obsidian

It also says its very brittle...

I'm not sure about the benefits, because it isn't clear what the differences between obs and normal glass is. One thing I do know is that you can make ultra sharp blade edges out of obsidian...I'm not sure you can do the same with glass.

To be honest I had a fairly random stoned idea, which I've no doubt I'm never going to follow through with, so I might as well explain. I was interested in re-kindling the idea of using obsidian for scalpels. If it were possible to cast obsidian accurately (which I'm beginning to get the feeling it isn't!) then it might theoretically be possible to mass produce very uniformly shaped obsidian pieces.

In theory, if the casts were designed right, the cutting edge could be produced from these pieces by casting them so they have one main cleavage or weakness line, which could be snapped off on first use.

There are obsidian scalpels out there, but they tent to be hand-knapped, which makes them impossible for the FDA to approve for use in surgery. Mass production could have a shot at changing that. They are far better than steel, but tend to be fragile...something else which might be able to be improved if obsidian could be cast...

Anyway. Stoned idea, which I always knew was pretty "out there"

Send a few bucks my way if anyone reads this and makes their billions though eh! hehe

Seems like obsidian scalpels would be pricey. Is there a problem with metal scalpels? Does it cut better?

Yeah. The cutting edge is significantly narrower at its tip than you get with steel, and the edge is smooth when viewed under a microscope. Metal blades look jagged, almost serrated under very strong magnification.

So if a surgeon uses an obsidian scalpel then there is less risk of scarring. Obsidian blades are sharp enough to split cells in half, where steel just rips and tears cells apart. It could be useful in delicate surgery for that reason. I probably isn't cost effective though, since the improvement over metal is offset by the fact it can only be used on soft tissue and you need to be careful not to break it...and it's seems impossible to make them cheaply with mass production.

You can buy a professional obsidian scalpel for $80. So if you could make them cheaply and increase their usage then there would be money in it...potentially! haha

As I said...just stoned chat really...

Splitting cells. Sounds intense. You know any surgeons?