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Hi all. Please excuse the sophmoric nature of this question, but reading has piqued my curiosity and something isn't clear to me.
1.) What's the difference between an occlusion vs. and inclusions? (I understand them to be the same thing)
2.) Are occlusions/inclusions relegated only to the world of natural stones or are they seen in the synthetic hone world as well?
Again, sophmoric, but I can think of finer crew and it's bugging me.
Bombs away! :rofl2:
Kind Regards,,,
I never heard of an occlusion in geological terms that sounds more like a medical condition. An inclusion is kind of what the word means. Usually within a rock or mineral are other minerals. A good example is rutilated quartz which is quartz with usually needle xtls of the mineral rutile inside it. With honing stones you could have a particular mineral included into the matrix.
And that mineral could either be harder than the hone material or softer, the later posing absolutely no thread to the edge, right?Quote:
Originally Posted by thebigspendur
How 'bout taking a stab at number 2.) ?
And, yes, I believe one must be a patient of an opthomologist to properly understand occlusion.
The inclusion can be harder or softer or the same.
As to synthetics, I'm afraid I didn't study that in Geology classes. Having said that synthetics are man made so they should be uniform and consistent.
One of the ways you can tell a synthetic gem from the natural kind is the synthetic is too perfect. The natural will have flaws of some kind as well as some inclusions.
"Occlusion (dentistry), the manner in which the upper and lower teeth come together when the mouth is closed."- Wikipedia
How does that relate to hones? Isn't it obvious?
My understanding from a quick search of my old chemistry texts is that an inclusion is when the impurity is actually part of the crystal structure. An occlusion is when the impurity is trapped within the structure. It reads as though it is a strength of bond thing - occlusions are weakly bound. Maybe someone who actually knows about chemistry can confirm, deny or clarify.
But assuming I understood it correctly, I think from a hone point of view they both basically boil down to one thing - impurity in the hone. I suppose some impurities can be good, some can be bad, some can be benign. If I'm right, an inclusion, if bad, can be hard to get rid of because it is part of the crystalline structure of the rock. An occlusion, being an impurity trapped within the structure, might release into the water after being dislodged? Just guessing.
I cannot see why, even with man made manufacturing processes, you couldn't at least get occlusions. Maybe even inclusions, but they may need to be present already in whatever media is being used to construct the hone. Though if they are, my understanding of the hone making process is that any inclusions in the raw materials would be broken down during that process so you wouldn't get long veins of it or whatever.
Anyway, all this theorising is predicated on the assumption that I've correctly understood inclusions and occlusions in the first place. And that could be a big assumption, since it's still not 7am here...
James.
Never read any old texts using the word 'occlusion' but the stuff I read tends to be hone-specific whereas something more technical may well use terms we are unfamiliar with.
Some inclusions are not that bad. Take the highly figured charnley forest hone, for example. The deep red swirls (not the thin red veins) often have a black or darker spot in the middle where you may find what the old texts called "pinny inclusions".
These hard, pin-like crystalline inclusions are harder than the rest of the hone and can scratch or sometimes chip the bevel. However, they are usually few in number and may be prised out of the softer red material with the tip of a knife.
The resulting small cavity is of no consequence when honing.
Regards,
Neil
The two naturals that I have don't have any obvious inclusions. How can you tell the difference between that pattern that the stone may have vs. an inclusion. Being a crystal, will they reflect light differently than the rest of the stone?
I think, in the majority of cases, it is hard to judge. Some naturals have lots of sparkly bits - quartz, mica, etc, that does no harm at all. The Special Hone for Good Razors is definitely sparkly and I have seen a lot of slates, including thuringians, with sparkly bits.Quote:
Originally Posted by OCDshaver
Even some hones that may look quite homogeneous to the eye when dry reveal banding and speckling when wet - the small Celebrated Water Stones often display this effect and Hatzicho has posted wonderful pics of thuringians like this.
In some respects any patterned, veined or spotted hone contains inclusions, otherwise it would be the same colour all the way through.
One stone that often had inclusions was the old Mueller Water Stone. The old variety could be very good indeed and I used to sell them, but the occurrence of harmful (ie scratchy) inclusions was so common that I had to test nearly every stone I sold towards the end - then they became incredibly variable - quite poor in some respects dropping from a decent finisher to little better than mid range, that I stopped stocking them altogether.
The type of inclusions in those hones was either hard or impossible to see with the naked eye, or looked benign. The only way to tell for sure was testing the hone with a razor - a luxury most of us do not have. Then, the inclusion makes itself felt - you can literally feel it, and you can see its effect by examining the scratch pattern on the bevel, where the inclusion leaves usually widely separated deeper score-marks, being harder than the rest of the matrix.
In short, testing is the only sure way.
Regards,
Neil
Obviously the patterns, spots, veins are some form of variation in the make up of the stone but does that necessarily mean that its due to inclusions? Or maybe my understanding of inclusions is incorrect? Or is the crystal/harder material the definition of toxic (another term I'm not 100% sure about)?Quote:
Originally Posted by Neil Miller
The rocks we are concerned with are mainly sedimentary - ie, particles laid down in water over a vast number of years, hardened by induration or some other metamorphic process, and either brought to the surface or mined. Who knows what was in the air at the time of their formation? Particles of all sorts from volcanic eruptions, silty run-off from vast distances away during flooding, etc, etc. So the elemental particles are not 100% pure - they are a mixture to begin with.
In a lot of instances you get ferric or ferrous particles in the original mix. In the case of purple slate from Wales it is not uncommon to see a green spotted or lenticular appearance as ferric reduction takes place around the original iron particle nucleus.
In others slates we find pyrites - scratchy inclusions, 'toxic' or bad if you like.
In others there was some amount of cleavage and cracking during their formation, allowing water bearing other minerals in solution to get into the cracks - the black lines and dots of manganese oxide inclusions in yellow coticules are an example, although harmless or benign, of this type of inclusion.
In geology, the term inclusion is a bit 'loose' inasmuch as it means anything included. However, one type of inclusion known as a 'clast' exists in which we get bits of other, older rocks, etc, in newer rocks. To explain how this happens imagine a silty strata being laid down in a river bed. Further upstream there are rocks that have already undergone full formation/transformation. During a raging downfall torrents of water wash down bits of these older rocks and lay them on the silt layer. The silt layer continues forming for thousands of years, then is transformed itself into rock - with bits of other rock or mineral in it.
Regards,
Neil
I totally agree Neil & one cannot understate the effect that Dinosaur Flatulence had on forming some of our favorite finishers; take the coticule for instance, put yourself in a small room & slurry it for an hour or two. You'll see what I mean,,,:shrug:Quote:
Originally Posted by Neil Miller
You mean you have coprolites in your hones?Quote:
Originally Posted by Hirlau
Rocks are always being recycled. It's all part of the weathering process on our plant. Whether it's through sedimentation at the surface or what goes on deep in the earth it's a continual process. When you're dead and buried you may become part of that process too.
Remember, there is a difference between rocks and minerals with rocks being collections of minerals. Minerals are relatively homogeneous like Quartz for instance which is SiO2 while Granite for instance is a Rock which is made up of Quartz and Feldspar and Mica and other things for good measure thrown in.If you saw some Quartz with enough magnification you would see all the actual hexagonal xtls all nicely arranged within the matrix. If the growth conditions are perfect you have the outward expression of that with a nice looking quartz xtl like you see in books. Rocks are just a mass. Back in the old days in the Petrology Lab we would slice rocks and grind them down to paper thinness to make a thin section and look at them in a polarizing microscope and the different minerals could be easily observed.
So depending on what your hone is and what it's physical properties are and the chemistry is you can have all sorts of things going on inside your hone. Some good and some bad.
Excellent info in here.
I think this is why I (and maybe others too) am fascinated with natural hones for more than just their ability to sharpen metal. The geological processes may be well-defined but those random little inputs to the process over time and space can and do produce some spectacularly interesting rocks.
James.
The thing is, my dear Hirlau, that fossilised poo, aka coprolites, does not smell!Quote:
Originally Posted by Hirlau
So, I put it to you that if you sit in a small room and smell a characteristic odour you imagine is coming from your hone, the chances are that you need your hearing tested and/or a change of underwear!
To be serious for a moment (and placate the Great & Wise Oz) this does have a small bearing on razors.
In the late 1820s Peruvian guano (phosphate rich bird droppings, partly digested fish and bird skeletons) were found to be a fine source of fertiliser. Enterprising individuals imported it by the boatload and fortunes were made. Eventually the cost became prohibitive and cheaper alternatives were sought.
In the 1840s on the Uk coast at Felixstowe and all along the mouth of the River Orwell a seam of coprolites was found. It was so large and extensive that whole long-lived industry grew up based on its use as agricultural fertiliset by virtue of its high phosphate content.
But where do razors come into it, I hear you cry. The answer lies with the refuse of Sheffield's knife and razor industry, namely in the waste arising from bone handles and scales. The cuttings were buried until someone noticed they made plants grow better, then around 1830 a bone meal, powdered bone and burnt bone based fertiliser industry grew up.
Demand soon outstripped supply, and Britain scoured the world for old bones. Boat loads of mummies from Egypt were ground down. Once, a burial ground for mummified cats and other pets was found in Egypt, the enterprising finder selling the lot, around 80,000, to the UK.
All things are interlinked, it seems...
Regards,
Neil
I dunno Neil, that link is tenuous at best. Not sure you're gonna fool Oz with that, he's quite sharp.
On an unrelated topic, I recently discovered a vein of naturals down my back yard. I'm gonna call them "Poo-ringians" because they are soft and have sort of a brown-blue colour like their German namesake. No need for water, they are already kind of wet. Actually, they may be better used in paste form ... :thinking:
James.
Some really great info and discussion going on here, fellas. I really appreciate the posts
:popcorn:
You're welcome Siguy,,,:tu
I'm just glad my vast wealth of knowledge on naturals helped out,,,:shrug:
First I have been following this thread intensely and thank those who have contributed there accumulated knowledge with us, great stuff guys.Quote:
Originally Posted by Jimbo
On to James,
I have a strop for that and I will send it to John for testing, please also submit your sample to Attn: Hirlau at.........
Pat,Quote:
Originally Posted by pfries
That would be sent Attn: Hirlau, the Wise
"Pay no attention to that man behind the curtain." :)Quote:
Originally Posted by Neil Miller
Thunder & lightining abates & link follows to a similar thread.
http://straightrazorpalace.com/hones...ml#post1003513
Yep. Was there in the Way Back machine before posting. The Grate-poweredful Oz has spoken!
OK Oz, I have enough trouble with one window opened to searching SRP, you leading me to two....
Is this like a drug where you build a tolerance and need more to get the same out of it.....
Dang SRP Pushers your behind all the AD disorders aren't you :cry:
Just information. :)Quote:
Originally Posted by pfries
The color is simply a reflection of chemical bonding of certain strength (more precisely differences in bonding, so when the electrons get bumped into higher energy state and then fall back to the lower state the energy difference is emitted as light of particular energy/frequency/wavelength/color).Quote:
Originally Posted by OCDshaver
The visible spectrum is only between roughly 800nm and 400nm, so any other wavelength is invisible.
Now, what can be the reason for particular difference in chemical bonding can vary immensely. Could be impurities of different materials, or defects in the crystalline structure, boundaries from poly-crystals, etc.
However, at the end of the day both the mechanical and the optical properties are the result of the same thing - how the electrons glue the nuclei.
It is extremely complicated problem and no umbrella statement is true.
You can have visually different colored areas on the hone surface have the exact same mechanical (abrasive) properties (to the precision we are concerned), and you can have visually uniformly colored surface have areas with different abrasive properties. For example the diamond particles on your hone could be white, or yellow, or brown - they would cut exactly the same way provided they are the same size. Or corundum, ruby, and sapphire look vastly different yet, if you'd use them for honing they'll perform the same (again given the particle sizes are the same)
Still in many cases when you see variations of color there could be differences in the abrasiveness, like the examples Neil gave. You just have to go on a case by case basis.
Another reason for changes in colour when the matrix contents are basically the same is the chatoyance effect,
This is mostly seen in gemstones, in fact the term means to shine like a cats eye and it is seen in that gemstone as well as tigers eye stones. The effect is best seen in gemstones with a curved or cabochon cut and in quartz with fibrous inclusions.
The effect can be seen in some glasses and a number of polished timbers. People describe it has having a 3D effect, as 'popping the grain' etc.
The hone stone that I have seen it displayed most often on is the Charnley Forest. When lapped to a fine degree you sometimes get the effect of being able to see below the surface of the stone, as well as shifting light and dark grain effects and variegated colours.
Regards,
Neil
Yes, I agree Jimbo, just like a toxic inclusion... :)Quote:
Originally Posted by Jimbo
...only joking Oz, old mate, dear pal, best buddy..)
Sincerely,
Neil
Also, some minerals are naturally dichroic and pleochroic so they can exhibit a variety of colors and the colors can be dramatically different. A good example is Tanzanite. The good original stuff was deep blue but it has flashes of green and red in it.
Then there is also a different case like Opal for instance. Common Opal is just a grayish-white mass of quartz but gem Opal has minute cracks filled with water which refracts the light causing the color.
Then there's fluorescent minerals too. It gets complicated this color thing.
Kinda like where this ends up ........ :DQuote:
Originally Posted by Neil Miller
KING CLAUDIUS Now, Hamlet, where's Polonius?
HAMLET At supper.
KING CLAUDIUS At supper! where? 19
HAMLET Not where he eats, but where he is eaten: a certain
convocation of politic worms are e'en at him. Your
worm is your only emperor for diet: we fat all
creatures else to fat us, and we fat ourselves for
maggots: your fat king and your lean beggar is but
variable service, two dishes, but to one table:
that's the end.
KING CLAUDIUS Alas, alas!
HAMLET A man may fish with the worm that hath eat of a
king, and cat of the fish that hath fed of that worm.
KING CLAUDIUS What dost you mean by this?
HAMLET Nothing but to show you how a king may go a
progress through the guts of a beggar. 31
KING CLAUDIUS Where is Polonius?
HAMLET In heaven; send hither to see: if your messenger
find him not there, seek him i' the other place