Naked Science Forum

General Science => General Science => Topic started by: Seany on 12/05/2007 17:09:36

Title: Diamonds are not Scratchable!!
Post by: Seany on 12/05/2007 17:09:36
My dad always said that diamonds are so strong, that they cannot be scratched with a pin, rock or anything. However, if you use a hammer, it can crack. It's like a putty, if you use your fingers slowly to squash it, it squashes. But if you use a hammer, it remains firm.

But I still don't believe that diamonds are not scratchable.

Would anyone here want to do an experiment? Heehee.. Oh by the way, if the conclusion comes that the diamond does scratch, I am taking no responsibility for it! [;)] Heehee
Title: Diamonds are not Scratchable!!
Post by: JimBob on 12/05/2007 18:06:35
One diamond can scratch another. They are the hardest NATURALLY occurring stone - see Mohs Hardness Scale -- http://en.wikipedia.org/wiki/Mohs_Hardness_Scale

Synthetic materials may be harder, but There is still an argument among some geezers about whether they should be counted as that do not occur in nature.  They also have an very hard crystalline lattice and do not compress as putty does.
Title: Diamonds are not Scratchable!!
Post by: Seany on 12/05/2007 18:07:33
Oh, I forgot to mention that.. I knew that one diamond can scratch another!
Title: Diamonds are not Scratchable!!
Post by: Seany on 12/05/2007 18:08:23
Hmm.. But can you try it out for me? Use a rock against a diamond to see if it scratches!
Title: Diamonds are not Scratchable!!
Post by: JimBob on 12/05/2007 18:37:06
Alas, sigh, I am rich in friends only. Hit up 'ol Uncle Neil, he is the money bags around here. He may do it for science!!


BUT DON'T HOLD YOUR BREATH !    [xx(]

Title: Diamonds are not Scratchable!!
Post by: Soul Surfer on 12/05/2007 19:05:29
There is a material that has been claimed to scratch a diamond.  It is boron trinitride sometimes called borazon.  It has a crystal structure similar to diamond although I think that it was eventually proved that it is only hardenough in some directions.

I first read this in new scientist back in the fifties but I have checked google and this is a wikipedia reference

http://en.wikipedia.org/wiki/Borazon

Title: Diamonds are not Scratchable!!
Post by: neilep on 12/05/2007 19:49:05
I'm not rich (Fiscally speaking)...but yes, Diamonds can of course be cut...they are every single day...using a diamond cleaver and only when hit at the right angle !....make a mistake and you have an expensive badly cut diamond  or expensive diamond bits !!

Only when I see my kids do I really know how rich I truly am !!
Title: Diamonds are not Scratchable!!
Post by: Karen W. on 12/05/2007 19:55:08
I'm not rich (Fiscally speaking)...but yes, Diamonds can of course be cut...they are every single day...using a diamond cleaver and only when hit at the right angle !....make a mistake and you have an expensive badly cut diamond  or expensive diamond bits !!

Only when I see my kids do I really know how rich I truly am !!

Is that not the truth or what!!!! They are great!!!The Best wealth the world has to offer!!!YAYYYYYYYYYYYYY! Me too Neily.. ME TOO!!
Title: Diamonds are not Scratchable!!
Post by: Seany on 12/05/2007 19:57:12
I'm not rich (Fiscally speaking)...but yes, Diamonds can of course be cut...they are every single day...using a diamond cleaver and only when hit at the right angle !....make a mistake and you have an expensive badly cut diamond  or expensive diamond bits !!

Only when I see my kids do I really know how rich I truly am !!

Aww how sweet Neil! [;)] Would you risk scratching a diamond with a rock though? [;)]
Title: Diamonds are not Scratchable!!
Post by: neilep on 12/05/2007 20:14:07
I'm not rich (Fiscally speaking)...but yes, Diamonds can of course be cut...they are every single day...using a diamond cleaver and only when hit at the right angle !....make a mistake and you have an expensive badly cut diamond  or expensive diamond bits !!

Only when I see my kids do I really know how rich I truly am !!

Aww how sweet Neil! [;)] Would you risk scratching a diamond with a rock though? [;)]

I'd give it a try but it would have to be MY diamond !!...I do handle them...but I don't own them !!.....wish I did !!..
Title: Diamonds are not Scratchable!!
Post by: Bass on 12/05/2007 22:52:24
I know that diamonds on diamond drill bits wear down with use- probably not from being scratched, but rather by knocking off very small chips (similar to rocks being rounded by streams).
Title: Diamonds are not Scratchable!!
Post by: neilep on 12/05/2007 23:07:16
Yes, just because something is very hard, does not mean it is impervious to the results of friction and every day wear and tear !

......well...except wifeys sponge cake...now that IS hard !!!
Title: Diamonds are not Scratchable!!
Post by: Seany on 12/05/2007 23:20:08
Well.. I'll be telling your wife on that!! [;)]
Title: Diamonds are not Scratchable!!
Post by: Bass on 12/05/2007 23:46:28
Neil- I'll match my wife's fruit cake to your sponge cake anytime [:P]
Title: Diamonds are not Scratchable!!
Post by: lightarrow on 13/05/2007 12:15:01
My dad always said that diamonds are so strong, that they cannot be scratched with a pin, rock or anything. However, if you use a hammer, it can crack. It's like a putty, if you use your fingers slowly to squash it, it squashes. But if you use a hammer, it remains firm.
But I still don't believe that diamonds are not scratchable.
Would anyone here want to do an experiment? Heehee.. Oh by the way, if the conclusion comes that the diamond does scratch, I am taking no responsibility for it! [;)] Heehee
Maybe it'll sound quite strange to you, but you don't need an harder material to scratch diamond; you can exploit kinetic energy. You know, even the very soft lead can make holes in a steel plate or whatever material, if you shoot it with a rifle.

The same principle can be used to work on diamonds: a fast rotating wheel made of some hard material (not necessarily Very hard), which will consume during working, will take away little pieces of diamond.

They say you can even cut glass with a fast rotating disk made of tick paper!

Physics, fascinating, isnt'it?
Title: Diamonds are not Scratchable!!
Post by: Seany on 13/05/2007 12:26:58
Yes.. But there is a difference between taking away pieces of diamond (cracking) and scratching it. Well, scratching it is taking away tiny tiny tiny tiny pieces of diamond, but it is not cracking it into tiny pieces. It's scraping off the surface of the diamond.
Title: Diamonds are not Scratchable!!
Post by: lightarrow on 13/05/2007 13:13:17
Yes.. But there is a difference between taking away pieces of diamond (cracking)
Why do you call it "cracking"?
Quote
and scratching it. Well, scratching it is taking away tiny tiny tiny tiny pieces of diamond, but it is not cracking it into tiny pieces. It's scraping off the surface of the diamond.
I don't understand what you mean. Diamonds can be cut without using cleaving, using a fast rotating disk made of bronze:
http://science.howstuffworks.com/diamond1.htm
Quote
Sawing - Sometimes, diamonds have to be cut against a cleavage plane, which cannot be done with cleaving. Using a phosphor-bronze blade rotating at about 15,000 rpm, the saw slowly cuts through the diamond. Lasers are also being used to saw diamonds.
Title: Diamonds are not Scratchable!!
Post by: Seany on 13/05/2007 13:19:20
I couldn't find a right word instead of cracking.. I mean.. Like crumbling into pieces..

Scratching means that little tiny paticles are scraped off the surface of the material.