Diopside belongs to the pyroxene family, monocline system, and the crystal is short columnar, transparent to opaque, with glass luster.
The color is light green to dark green. With the increased iron content, the color will deepen to brown or even black.
Diopside is a common mineral, but there are few gem-grade crystals. The well-crystallized crystals are mainly produced in marble and kimberlite.
However, the vast majority of gem-grade crystals in the market are mainly from Myanmar and Sri Lanka.
Basic properties of Diopside
1) Composition: calcium magnesium silicate( CaMg (SiO3) 2).
2) Crystallization characteristics: monoclinic system. When the crystal is well developed, it is columnar, coarse and short columnar. There are also crystal fragments and water-eroded pebbles.
3) Color: colorless, gray, light green, dark green, brown and black.
4) Variety:
Chromium diopside: it is bright green, and the color is caused by chromium;
Star diopside: it is black, and it is asymmetric starlight;
Violane: It is small and dark purple and blue, which is very rare.
5) Spectra: Chromium diopside shows the chromium spectrum. There is a double line (690nm) in the red area, three weak absorption bands at 635nm, 655nm and 670nm, an absorption line at 508nm and 505nm in the blue-green area, and an absorption band at 490nm. The spectrum of other varieties is not typical.
6) Optical effects: Cat’s eye and starlight effects.
7) Luminescence: blue or milky white and orange-yellow fluorescence under SW ultraviolet light; LW sometimes emits light purple light under ultraviolet light.
8) Origin: It occurs in metamorphic rocks and kimberlites rich in Ca (chrome diopside); It is produced in Brazil, Italy, Myanmar, South Africa, Siberia, Pakistan, India, etc.
Different types and characteristics of Diopside
Common Diopside
Composition: The simple chemical formula is Ca (Mg, Fe) [Si2O6], which contains less than 10% Fs and A1, Fe3+, Cr, Mn, V, Ti, Na, etc.
If the content of Cr2O3 is 0.3%~1%, it can be called chrome-containing Diopside; if the content of Cr2O3 is more than 1%, it can be called chrome diopside.
Form: monoclinic system. The crystals are mostly short columnar and granular, and the aggregates are sometimes radial. It has pyroxene-type cleavage. {100} and {001} cleavage can be seen.
Luminosity: Most of them are light green and dark green, and the chrome diopside is emerald green. Those who reach gem level can make emeralds.
The thin section is colorless and transparent, and the chrome diopside is light emerald green with slight polychrome.
Positive protrusion. Np=1.665~1.678,Nm=1.672~
1.693,Ng=1.696~1.709，Ng-Np=0.031. The highest dry color is Grade II orange. Monocline type extinction type, Ng ^ c=38 °~41 °.
Simple twin, flake twin and exsolution foliation can be seen. Two axis (+), 2V=50 °~59 °.
Change: It is easy to change into chrysotile, chlorite, serpentine, talc, biotite, and carbonate.
Occurrence: As a metamorphic mineral, it occurs in sandstone, impure magnesia marble, pyroxene hornstone and some regional metamorphic rocks.
Salite
Salite is named after the place where it was first discovered, Sala, West Manland Province.
Composition: The simple crystal chemical formula is Ca (Mg, Fe) [Si2O6], which contains more Fe than Diopside, and its chemical composition is between diopside and calcium iron pyroxene; Fs=10%~25%.
It can be further named according to TiO2 content: those with TiO2<1% are Salite;
TiO2=1% ～ 3%, which is titanium-bearing Salite; TiO2>3% is titanium Salite.
Those with more (25%~40%) Fs than Salite are called iron Salite. Iron Salite is rare in nature.
Form: similar to Diopside.
Cleavage: There are two sets of complete cleavages.
Lightness: dark green. Light tone and polychrome are not shown in the thin film;
Those with more iron are light green to light brown, with weak polychrome.
Positive protrusion. Np=1.678~1.696，Nm=1.693~1.706，Ng=1.709~1.727，Ng-Np=0.031。
The highest dry color is related to grade II orange. Oblique extinction, Ng>c=41 °～ 43 °. Two axis (+), 2V=51 °~54°。
The refractive index of iron Salite is high: Np=1.696 ～ 1.715, Nm=1.706 ～ 1.724, Ng=1.727 ～ 1.746, Ng-Np=0.031.
The highest dry color involved grade II orange – grade II orange-red. Oblique extinction, NgAc=43 °~47 °. Two axis (ten), 2V=54 °~61 °.
Change: It is easy to change into uralite, chlorite, epidote, carbonate, etc.
Occurrence: It occurs in alkaline olivine basalt, olivine basalt, picritic basalt and tholeiite, and mostly occurs as phenocrysts;
The difference between Diopside and Salite
Salite’s crystalline morphology and optical properties are very similar to Diopside’s. The differences are: the protrusion of Salite is slightly higher, and 2V is slightly larger; If it contains more, it will be light purple. With the chemical analysis, we can accurately identify the refractive index and 2V.
Chrome diopside
ChromeDiopside contains trace chromium chromogenic elements. Other sister stones of chromium diopside include:
Baikalite: green, produced in the former Soviet Union;
Alalite: green to light yellow, produced in Alaualley, Italy;
Star diopside: a dark green tetragonal star diopside produced in India;
Cat’s eye diopside: dark green background, produced in South Africa, Sri Lanka, Madagascar, Canada, Canada and the United States.
The difference between Star diopside and Cat’sCat’s eye diopside
The star effect of star diopside is usually four starlight phenomena on the black body color, which intersects at 75 and 105 degrees.
The directionally arranged magnetite needles produce starlight. At the same time, it is one of the characteristics of starlight diopside that it has magnetism.
The Cat’sCat’s eye effect of Cat’sCat’s eye diopside is a unique phenomenon because it contains a large number of directionally arranged tubular inclusions, starlight diopside or sheet inclusions.
In addition, when cutting and grinding star diopside, the Cat’sCat’s eye can also be formed by keeping the single line optical effect at an angle.
Starlight and Cat’sCat’s eye type of Diopside is mainly produced in India and are good gemstone in the jewelry industry.
The difference between Diopside and augite
Diopside is very similar to augite. In basalt, they often coexist and are easy to mix, which can be distinguished from the following aspects:
A)The axis of Diopside is more developed than that of cylinder, and the cross-section is nearly square octagon, while the axis and cylinder of augite are equally developed, and the cross-section is nearly regular octagon.
B)The extinction angle of Diopside is usually less than 40 °, while that of augite is more than 40 °; The former has a smaller extinction angle.
C)The maximum birefringence of Diopside is greater than 0.029 and that of augite is less than 0029; The former has higher interference color.
D)There are also differences in occurrence between the two: Diopside can be either a metamorphic mineral or a magmatic rock mineral, while augite is mostly a magmatic rock mineral;
In magmatic rocks, Diopside mostly occurs in alkaline rocks. When the two are symbiotic, Diopside mainly occurs as phenocrysts.
Diopside Healing Energy
Diopside is derived from the Greek “dis” (double) and “opsis” (image), representing that its crystallization can form a double image.
Most of diopsides have Cat’sCat’s eye phenomenon because their contents can be arranged regularly to form linear flashing light under light irradiation.
If the Cat’sCat’s eye phenomenon appears in two directions and forms a cross, it is called a cross star diopside stone, together with Chiastolite and staurolite, which is the holy stone of Christianity.
Cross star diopside stone belongs to the monoclinic system, which can bring soft and stable supplementary energy, help us transform negative emotions, and also keep our focus.
The properties of the cross-stone can also help us find out the root of the problem, really deal with the internal emotional issues, and face our own fears rather than escape.
How to use
When we feel that our life is turbulent and restless, or when people or things around us change dramatically and become abnormal, we can use the cross star stone to make the energy become stable and simple and no longer lose control easily because of external influences.
For people with emotional problems or mental disorders, this healing stone can help us stabilize our emotions and try to pull ourselves back into the real world.
When to use
Wake up from daydreams
when you need to stabilize your mind
focus attention
How to clean
Purification mode
Except for the sea salt method, other purification methods are available.
Conclusion:
Diopside is a member of the pyroxene family. It belongs to the monoclinic system. This kind of mineral crystal presents perfect two-way cleavage. The family members’ dark green and transparent varieties can be used as gemstones.