How are the Stones introduced to the client during the treatment?
· Surface ('bulk') diffusion-treated corundums (SDTCs) created a stir in the Bangkok corundum market in 1990. This article looks at the original Linde patents and continues through the so-called "Deep Diffusion" treatment. Identification methods are discussed, as well as the backroom politics of disclosure. At the end is a quick-reference table summarizing key …
How to avoid cross infection in stone therapy treatments?
Molecular diffusion, often simply called diffusion, is the thermal motion of all (liquid or gas) particles at temperatures above absolute zero.The rate of this movement is a function of temperature, viscosity of the fluid and the size (mass) of the particles. Diffusion explains the net flux of molecules from a region of higher concentration to one of lower concentration.
What is stone therapy?
· 13. B28 Provide Stone Therapy Treatments Knowledge & Understanding Assignment iii) Briefly describe the structure & functions of the following tissues: Tissue …
Which areas of the body need particular care when undertaking stone therapy?
· Reduced renal perfusion, attributable to hypovolaemia, hypotension, or drugs, which is reversible on correction of the underlying cause. Intrinsic Commonly results from …
What does diffusion mean on a gemstone?
Lattice diffusion is a treatment process that uses heat and chemicals to diffuse an element into a gemstone to artificially change its color. Lattice diffusion–treated sapphires can be any color. In some cases the added color is shallow. In others, it goes all the way through the stone.
What is diffusion stone treatment?
Diffusion treatment consists of exposing the surface of a stone to certain chemicals combined with high heat in a furnace. Generally, only the surface color changes, so if you sliced the gem in half, the inside of the stone would be a different color, usually a paler, less valuable color.
Is a diffused sapphire valuable?
Sapphires that have obtained their color from diffusion treatments have little intrinsic value. Reputable dealers will identify diffusion-treated sapphires and offer them at prices well below those of natural, untreated stones.
How do you find the diffusion treatment of sapphires?
Blue diffusion-treated sapphires are be- coming more prevalent than ever before. The diffusion technique, which involves the addition of color-causing chemicnls during heat trentment, results in a thin layer of color at the surface of colorless or light-colored sapphire.
What does diffusion mean in jewelry?
Diffusion is a technique whereby certain natural elements, those used in nature when colouring allochromatic gems, are placed on the surface of the gem during the heating process and the colour is diffused into the gem.
What is diffused jewelry?
A diffused stone uses a chemical element to score the surface of the stone, then combining it with the heat of a furnace it is baked into the stone. This changes the color of the stone, often making it a richer color/more sought after stone.
Are treated gemstones less valuable?
Treated gemstones are cheaper. Most people want to buy or wear an emerald but since an emerald costs $50K per carat (untreated), most people cannot afford it. The solution is a treated emerald that starts at $10 per carat and can go up to $10K per carat.
How do you tell if a gemstone has been heat treated?
Heat treatment is a very risky process as many gems have inclusions that expand at a different rate and cause stress fractures, which then becomes an identifying characteristic of heated gems, particularly sapphire and ruby which can display halos around inclusions within the gem.
How can I tell if my sapphire is real?
Use a magnifying glass or a jeweler's loupe to check for impurities and flaws within your sapphire. Check for small flaws or specks within the stone. These are an indication that your stone is real. Lab-created sapphires are generally flawless in their composition.
Are unheated sapphires better?
In very short detail, an untreated sapphire is one that has been taken from the ground and then faceted. Nothing at all was done to the stone to alter the natural beauty, which only elements and process in the earth created naturally. These sapphires are exceptionally more rare and valuable.
What is diffusion Star Sapphire?
The gemstone used to make a diffused star sapphire is a sapphire. The diffusion process is done on the surface of the sapphire gemstone and could extend to around a millimeter into the gemstone. The process is done to create the star effect on the gemstone and the gemstone is then called a diffused star sapphire.
How much is a 2 carat blue sapphire worth?
A top-quality 1- to 2-carat stone might retail between $800 to $1,200 per carat. Quality 2- to 3-carat stones sell for about double that amount, around $1,600 to $2,000 per carat.
Where was surface diffusion done?
Further evidence of surface diffusion treatment being done in Thailand was presented to the author by a close friend, Robert Stevenson, who had sent some (non-Yogo) Montana sapphires to his friendly neighborhood Bangkok burner for cooking sometime about 1980–81. Before treatment, the stones were pale green-blue.
What was the first shot fired across our bow in the Battle of the Surface Diffusion Sea?
The anonymous pamphlet was just the first shot fired across our bow in the Battle of the Surface Diffusion Sea. Coupled with the one misidentification by AIGS on an ordinary heat-treated sapphire, rumors began circulating that AIGS had its head well into the nether regions of its backside, to such a degree that "many heat-treated stones were being misidentified by AIGS as SDTCs." This latter statement is absolutely wrong; to the best of the author's knowledge, only one SDTC stone (the one already described herein) has been misidentified by the AIGS lab in Bangkok.
What is corundum top?
Top = Natural corundum (usually green sapphire, due to its low cost, but can be ruby or any other variety); often with obvious silk and/or straight, angular color zoning, designed to give the stone a natural appearance under magnification#N#Base = Verneuil synthetic corundum (any color)with curved growth lines and possibly gas bubbles in the synthetic portion. More rarely, flux-grown synthetic corundum is used (with the accompanying flux inclusions), but this is not often seen due to the higher cost. Most deceptive are doublets where both top and bottom are natural corundum.#N#Separation Plane = A distinct join will be seen completely unbroken around the entire stone. It is usually at the girdle, but may also be found on the pavilion, or even on the crown. The glue layer used to join the two pieces often shows curved brush strokes and flat gas bubbles; since the glue's RI is quite different from that of the corundum, it will stand out in high relief when the stone is immersed in methylene iodide. At times, a corundum may be seen with a crack penetrating across the entire stone and the question arises as to whether the stone broke apart during cutting and was glued back together. Use of the hot point under magnification may melt portions of the glue, causing the bubbles to expand and contract in the crack, indicating assembly. Soaking the stone in a mild solvent (such as alcohol or acetone) may dissolve the glue, thus proving assembly, but this is a destructive test.
How do fractured gems work?
Fractured gems are heated in the presence of a flux. The flux runs into the fractures, dissolves the walls of the cracks and redeposits the synthetic corundum inside the crack, healing it closed .. [For more on this, see Foreign Affairs] This is detected by the following:
Why do corundums have color?
Color in natural single crystals forms in bands or zones parallel to crystal faces, not along polished facets, because the stone was not faceted when it was growing in the ground. Despite the irrefutable nature of that last statement, some have attempted to hoodwink people into believing otherwise. But more about that later.
What was the name of the company that made corundum?
In the late 1940s, after the war was over, Union Carbide's Linde Air Products division continued making synthetic corundum, and it was during this period that an extremely astute employee, John Burdick, noticed in one of the boules a cloudy patch which later proved to be rutile silk.
Why do people use ruby oil on stones?
So-called 'ruby oil' from Thailand is used mainly to allow buyers and sellers of rough to see into the stone more readily (similar to wiping a stone on one's forehead – the oils of the skin allow a better view of a rough stone's color and clarity), rather than for deception.
How does diffusion work in fluid?
Transport of material in stagnant fluid or across streamlines of a fluid in a laminar flow occurs by molecular diffusion. Two adjacent compartments separated by a partition, containing pure gases A or B may be envisaged. Random movement of all molecules occurs so that after a period molecules are found remote from their original positions. If the partition is removed, some molecules of A move towards the region occupied by B, their number depends on the number of molecules at the region considered. Concurrently, molecules of B diffuse toward regimens formerly occupied by pure A. Finally, complete mixing occurs. Before this point in time, a gradual variation in the concentration of A occurs along an axis, designated x, which joins the original compartments. This variation, expressed mathematically as -dC A /dx, where C A is the concentration of A. The negative sign arises because the concentration of A decreases as the distance x increases. Similarly, the variation in the concentration of gas B is -dC B /dx. The rate of diffusion of A, N A, depend on concentration gradient and the average velocity with which the molecules of A moves in the x direction. This relationship is expressed by Fick's Law
What is the name of the type of diffusion that occurs in the absence of concentration?
Tracer diffusion and Self-diffusion, which is a spontaneous mixing of molecules taking place in the absence of concentration (or chemical potential) gradient. This type of diffusion can be followed using isotopic tracers, hence the name.
Why are the diffusion coefficients for chemical diffusion different?
The diffusion coefficients for these two types of diffusion are generally different because the diffusion coefficient for chemical diffusion is binary and it includes the effects due to the correlation of the movement of the different diffusing species.
What is collective diffusion?
Collective diffusion is the diffusion of a large number of particles, most often within a solvent .
How does chemical diffusion affect entropy?
Chemical diffusion increases the entropy of a system, i.e. diffusion is a spontaneous and irreversible process. Particles can spread out by diffusion, but will not spontaneously re-order themselves (absent changes to the system, assuming no creation of new chemical bonds, and absent external forces acting on the particle).
What is the end result of molecular diffusion?
Since the molecules are still in motion, but an equilibrium has been established, the end result of molecular diffusion is called a "dynamic equilibrium". In a phase with uniform temperature, absent external net forces acting on ...
What are some examples of diffusion?
Diffusion is of fundamental importance in many disciplines of physics, chemistry, and biology. Some example applications of diffusion: 1 Sintering to produce solid materials ( powder metallurgy, production of ceramics) 2 Chemical reactor design 3 Catalyst design in chemical industry 4 Steel can be diffused (e.g., with carbon or nitrogen) to modify its properties 5 Doping during production of semiconductors.
What is reduced renal perfusion?
Reduced renal perfusion, attributable to hypovolaemia, hypotension, or drugs, which is reversible on correction of the underlying cause.
How long does anuric phase last?
The anuric phase of ATN classically lasts 7–21 days, and recovery to pre‐insult levels of renal function can be expected, although some impairment of function may persist, particularly if there is a background of chronic renal insufficiency (see Outcomes section).
What is ARF in medical terms?
Acute renal failure (ARF) is a potentially reversible reduction in the capacity of the kidney to excrete nitrogenous wastes and maintain fluid and electrolyte homoeostasis, which usually occurs over hours to days. The initial clinical approach is identical in all patients—a thorough history and examination with simultaneous treatment of any life threatening features (for example, severe hyperkalaemia). Subsequent management should focus on determining the cause, which may demand specific treatment, maintaining the patient's volume status, and avoiding further nephrotoxic insults.
What are the main diagnoses of ARF?
Many patients with ARF present with other diagnoses. Dehydration secondary to gastrointestinal losses, pneumonia, bowel obstruction, and new impairment of functional capacity in the elderly patient are often the initial “on take” diagnoses, and a diagnosis of renal failure is only made when laboratory parameters are available later. The clinician should then ask themselves the following questions (see box 1):
Is ARF reversible?
ARF is usually reversible with rapid relief of obstruction, but the longer the delay the more the long term damage. Obstruction should be sought by history and examination, before proceeding to urgent ultrasonography of the urinary tract. Prostatic disease is a common cause of ARF in men. Obstructive urinary symptoms may be elicited, a palpable bladder or hypertrophied prostate found on examination, and/or urethral catheterisation may yield a significant residual volume. In women, carcinoma of the cervix may be detectable on vaginal examination. There may be a history of renal stone disease. Obstruction can occur more proximally (fig 11).
What is the diagnostic approach for AKI?
The current diagnostic approach of AKI is based on an acute decrease of GFR, as reflected by an acute rise in sCr levels and/or a decline in UO over a given time interval. 6–8Recently several biomarkers have been proposed for the diagnosis of AKI and these are in various stages of development and validation.9–12Nevertheless, it is not clear, if a single or multiple biomarker approach is necessary to diagnose the complicated and multifactorial aspects of AKI.13–16
When was AKI first used?
The term Acute Kidney Injury (AKI) was used for the first time by William MacNider in 1918 in a situation of acute mercury poisoning, but became the preferred term in 2004 when ARF was redefined with the now widely accepted consensus criteria known as RIFLE (an acronym of the Risk-Injury-Failure-Loss-End stage kidney disease).6,55
What is AKI in nephropathy?
Classification of AKI includes pre-renal AKI, acute post-renal obstructive nep hropathy and intrinsic acute kidney diseases. Of these, only ‘intrinsic’ AKI represents true kidney disease, while pre-renal and post-renal AKI are the consequence of extra-renal diseases leading to the decreased glomerular filtration rate (GFR). If these pre- and/or post-renal conditions persist, they will eventually evolve to renal cellular damage and hence intrinsic renal disease.
What are the causes of AKI?
In urban areas of developing countries, main causes of AKI are hospital acquired (renal ischaemia, sepsis and nephrotoxic drugs) while in rural areas it is more commonly a consequence of community acquired disease (diarrhoea, dehydration, infectious diseases, animal venoms etc.). Under-reporting of AKI especially in developing countries is also a major problem that relates with the true knowledge of its impact in many parts of the world.29
What is ARF in medical terms?
Traditionally, emphasis was given to the most severe acute reduction in kidney function, as manifested by severe azotaemia and often by oliguria or anuria. However, recent evidence suggests that even relatively mild injury or impairment of kidney function manifested by small changes in serum creatinine (sCr) and/or urine output (UO), is a predictor of serious clinical consequences. 2 – 5
Is AKI a single organ failure?
Recent evidence, in both basic science and clinical research, is beginning to change our view for AKI from a single organ failure syndrome to a syndrome where the kidney plays an active role in the progress of multi-organ dysfunction.
Why don't we replace resins?
We don’t replace resins because they are old. We replace them because the no longer work. The longer answer, however, is that you would have to have the resin analyzed. This involves taking the system apart and pulling a representative sample of the resin.
Is cation resin a softener?
I have often told customers that as long as cation resin is still there, it acts as a softener. But to what level of performance? Again, with a little assistance from the lab, the effects of aging on the properties of softening resin were measured and compared to that of new resin (see Table 4).
Is ion exchange resin more expensive than styrene?
Think of ion exchange resin as a large hotel with thousands of rooms. The hallways have to be large enough to move in furniture and guests or the rooms go to waste. Likewise, they should not be so large as to waste floor space. Economy also plays a role. DVB is several times more expensive than is styrene. This explains the higher cost of the higher cross-linked products.