al@gtx.com (0732) (06/15/87)
-> -> I have a strange request ... does anyone in netland know where I can ->get some of osmium? -> -> I have heard it is the most dense substance on earth, denser than ->gold or lead. I think it would be fun to have a baseball size hunk of it ->on my desk as a paper weight. -> I remember a few years ago (like maybe 20) that some brand of ball point pen was advertised to have an osmium tip. You could get a few hundred thousand old pens, castrate them, test them to see which balls are osmium (smell them?) and melt them down. But seriously, what property of osmium would make it a choice for a ball-point pen tip? -------------------------------------------------------------- | Alan Filipski, GTX Corporation, Phoenix, Arizona 85021, USA | | {ihnp4,cbosgd,decvax,hplabs,seismo}!sun!sunburn!gtx!al | -------------------------------------------------------------- "The perversity of Nature is nowhere better demonstrated than by the fact that, when exposed to the same atmosphere, bread becomes hard while crackers become soft."
beede@hubcap.UUCP (06/17/87)
in article <336@gtx.com>, al@gtx.com (0732) says: > > [...]osmium (smell them?) and melt them down. But seriously, what property > of osmium would make it a choice for a ball-point pen tip? The answer is obvious--since osmium is so dense, when dropped, the pen tends to land point first, damaging it so that another pen must be purchased. This sort of reasoning drives many manufacturing decisions :-) -- Mike Beede UUCP: . . . !gatech!hubcap!beede Computer Science Dept. ARPA: BEEDE@TECNET-CLEMSON.ARPA Clemson University INET: beede@hubcap.clemson.edu Clemson SC 29631-1906 PH: (803)656-{2845,3444}
larry@kitty.UUCP (06/17/87)
In article <336@gtx.com>, al@gtx.com (0732) writes: > -> I have a strange request ... does anyone in netland know where I can > ->get some of osmium? You can try the Alfa Products division of Morton Thiokol, located in Danvers, MA., but I doubt that they will sell directly to individuals. One gram of pure osmium in 60 mesh powder form costs approximately $ 93.00. The catalog number is 00246. Pure osmium is a skin irritant at room temperature, but is significantly toxic when heated in air at a temperature greater than 130 deg C. When so heated, osmium combines with oxygen in the atmosphere to form osmium tetroxide (a/k/a osmic acid). It is osmium tetroxide which has a pungent, disagreeable odor. > -> I have heard it is the most dense substance on earth, denser than > ->gold or lead. I think it would be fun to have a baseball size hunk of it > ->on my desk as a paper weight. Osmium is the densest metal, having a specific gravity of 20.1. I believe that a "baseball size" hunk of osmium would cost quite a few kilobucks, considering the above price per gram. > I remember a few years ago (like maybe 20) that some brand of ball point > pen was advertised to have an osmium tip. You could get a few hundred > thousand old pens, castrate them, test them to see which balls are > osmium (smell them?) and melt them down. But seriously, what property > of osmium would make it a choice for a ball-point pen tip? Osmium and its alloys are unusually resistant to wear and corrosion, and therefore make an ideal (but expensive) material for pen points. The effective resistance of osmium to rubbing wear is very high, and is far greater than one would predict from mere density. Osmium is used in pen points and nibs, meter pivots, electrical contacts, and phonograph styli. Osmium melts at about 2700 deg C. The metal is totally unworkable by conventional machining methods, and can only be shaped by grinding, melting and powder metallurgy. <> Larry Lippman @ Recognition Research Corp., Clarence, New York <> UUCP: {allegra|ames|boulder|decvax|rocksanne|watmath}!sunybcs!kitty!larry <> VOICE: 716/688-1231 {hplabs|ihnp4|mtune|seismo|utzoo}!/ <> FAX: 716/741-9635 {G1,G2,G3 modes} "Have you hugged your cat today?"
tiberio@seismo.UUCP (06/17/87)
In article <336@gtx.com>, al@gtx.com (0732) writes: > > -> I have a strange request ... does anyone in netland know where I can > ->get some of osmium? Osmium was used in early phonographic needles seismo!tiberio
jnp@calmasd.UUCP (06/19/87)
> -> I have a strange request ... does anyone in netland know where I can > ->get some of osmium? > I remember a few years ago (like maybe 20) that some brand of ball point > pen was advertised to have an osmium tip.... > ... But seriously, what property > of osmium would make it a choice for a ball-point pen tip? On the order of 25 years ago I read a short piece on Osmium in the Life Science Library book of Elements. As my weakening memory recalls, Osmium has a remarkably low melting point (near 100F I seem to recall). It has another odd quality - it causes metals like steel to become extremely hard, although brittle. I believe it is this hardness which causes its use in ball point pens. -- These opinions are solely mine and in no way reflect those of my employer. John M. Pantone @ GE/Calma R&D, Data Management Group, San Diego ...{ucbvax|decvax}!sdcsvax!calmasd!jnp jnp@calmasd.GE.COM
jelkind@ruby.berkeley.edu (The Unexpected Tiger) (06/21/87)
>> I have a strange request ... does anyone in netland know where I can >> get some of osmium? The form of Os that is generally commercially available is Os powder. It costs in the realm of $80 - $100 per gram. You should also know that Os powder oxidizes spontaneously in air to form the EXTREMELY TOXIC compound osmium tetroxide. >> ... But seriously, what property >> of osmium would make it a choice for a ball-point pen tip? As other people have mentioned, the property of osmium that makes it a choice for a ball-point pen tip is its extreme hardness and ability to form very hard alloys. >On the order of 25 years ago I read a short piece on Osmium in the Life >Science Library book of Elements. As my weakening memory recalls, Osmium has >a remarkably low melting point (near 100F I seem to recall). > >John M. Pantone @ GE/Calma R&D, Data Management Group, San Diego According to the Handbook of Chemistry and Physics (1981-82 edition), the melting point of osmium is 3045 +/- 30 degrees Celsius. Although the 10th edition of the Merck index reports its melting point as 2700 C, the catalogs I've seen quote the former value. In any case, Os is the *highest* melting platinum metal, and, accoding to the trusty CRC, is "very difficult to fabricate." Richard Schultz
brian@prism.UUCP (06/22/87)
If I added a small amount of Osmium to a metal that melts (say, zinc), would
it increase the hardness (like antimony does to lead)?
----
Brian K. Moran brian@mirror.TMC.COM
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Mirror Systems 2067 Massachusetts Avenue Cambridge, MA, 02140
Telephone: 617-661-0777 extension 141
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---chris@mimsy.UUCP (Chris Torek) (06/26/87)
On one journey through a dictionary---alas, I cannot recall which---I ran across the fascinating word `osmiridium'. The definition claimed that this was an alloy of osmium and iridium that is used in ball-point pens. So as long as people are expounding upon osmium, perhaps someone could verify or refute this. Thinking stray thoughts at 4 AM, -- In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7690) Domain: chris@mimsy.umd.edu Path: seismo!mimsy!chris
stumpy@sdcc6.UUCP (06/30/87)
In article <7213@mimsy.UUCP>, chris@mimsy.UUCP (Chris Torek) writes: > On one journey through a dictionary---alas, I cannot recall which---I > ran across the fascinating word `osmiridium'. The definition claimed > that this was an alloy of osmium and iridium that is used in ball-point > pens. So as long as people are expounding upon osmium, perhaps someone > could verify or refute this. also known as itidosmine this is a natural alloy of iridium and osmium containing some platinium, rhosium, ruthenium, iron, copper, and palladium. tin-white to light steel gray in color, this is found in california, oregon, russia, japan, and brazil just to name a few places. aside from being used as fountain pen tips, it also is found in surgical needles and watch pivots. the above was graciously paraphrased from the sixth edition (1961) of "the condensed chemical dictionary"