Sparkling Appearance Research Articles

A 23 carat alloy with a colourful sparkle

Lightly etched surfaces of specimens comprised of the Au-Al β′-phase exhibit a remarkable sparkling appearance and play of colour. An investigation of this phenomenon is described and explained here. The play of colour produced from individual grains as the sample is tilted in light is due to diffraction from arrays of very regular lamellae. However, consistently obtaining the desired microstructure requires an understanding of this alloy system’s remarkable behaviour. Other technological properties which would be relevant to possible commercial application of this alloy are also discussed.

Differentiation of Cardiac Amyloidosis and Hypertrophic Cardiomyopathy

The clinical and echocardiographic features of cardiac amyloidosis may closely resemble those of hypertrophic cardiomyopathy, and the disorders may thus be mixed up. The present study was undertaken in an attempt to identify features separating the two conditions by analysis of electro- and echocardiographic findings in patients with familial amyloid polyneuropathy and hypertrophic cardiomyopathy. Twenty-nine patients with familial amyloidosis and 22 with hypertrophic cardiomyopathy were studied. Particular attention was given to the sum of the S wave in V1 and R wave in V5 or V6, the echocardiographic left ventricular mass and cross-sectional area, the presence or absence of asymmetrical septal thickening, granular and sparkling myocardial appearance, thickened heart valves, systolic anterior motion of the mitral valve, and pericardial effusion. A granular and sparkling appearance of the myocardium and thickened heart valves were found to be the best predictors of cardiac amyloidosis, while low QRS amplitudes in relation to echocardiographic left ventricular mass and a pericardial effusion seemed less important. The presence of systolic anterior movement of the mitral valve, a large left ventricular mass and a sum of S in V1 and R in V5 or V6 greater than 35 mm indicated hypertrophic cardiomyopathy. When the four strongest predictors (left ventricular mass, thickened heart valves, a granular sparkling myocardial appearance, and systolic anterior movement of the mitral valve) were used to reclassify the present patients, 28 of 29 amyloidosis patients and 21 of 22 patients with hypertrophic cardiomyopathy were correctly categorized. Noninvasive methods may thus be useful for detecting the myocardial infiltrative process, and cardiac amyloidosis may be confidently diagnosed by typical noninvasive findings together with histopathological documentation of amyloid in an organ other than the heart.

Echocardiographic findings in systemic amyloidosis: Spectrum of cardiac involvement and relation to survival

One hundred thirty-two patients with biopsy-proven systemic amyloidosis underwent echocardiographic examination to define the spectrum of cardiac involvement. Echocardiographic abnormalities were then correlated with clinical variables and survival at follow-up. Patients were subgrouped by left ventricular wall thickness: Group I, mean wall thickness 12 mm or less; Group II, mean wall thickness greater than 12 mm but less than 15 mm; Group III, mean wall thickness 15 mm or greater; or Group IV, atypical features such as wall motion abnormalities or left ventricular dilation. Patients with greater wall thickness had a higher frequency of associated echocardiographic abnormalities such as left atrial enlargement or granular sparkling appearance on two-dimensional examination and, more commonly, reduced systolic function. The occurrence of clinical congestive heart failure was strongly correlated with greater wall thickness and multiple other echocardiographic abnormalities. Survival was negatively influenced both by greater wall thickness and reduced systolic function. The median survival of the entire group was 1.1 years. Echocardiographic examination is an important tool for establishing the presence of cardiac amyloid involvement and may be useful in estimating prognosis in such patients.

Zincian dolomite from broken hill, New South Wales

Abstract Many Broken Hill (New South Wales) specimens labelled ‘zinco‐calcite’ in museum and private collections are snow‐white, globular forms with a sparkling appearance, on a coronadite or limonite matrix. X‐ray diffraction and microprobe analyses show the globules have a core of nearly pure calcite, overlain by colourless, drusy zincian dolomite with up to 4 mol % ZnCO3 and up to 7 mol % excess CaCO3. Although Zn is abundant in the Broken Hill orebody, it apparently entered carbonate, mainly as smithsonite, only during formation of the oxidised zone.