form of crystal aggregates in afghanistan

Afghanite is a rare mineral with the only significantly important deposit being Sare Sang Kokcha Valley in Badakshan Province Afghanistan where it forms large and beautiful crystals that are almost always embedded on a white marble matrix Small crusts of Afghanite occur in the vicinity of Slyudyanka near the southern area of Lake Baikal and white and colorless microcrystals in the vicinity of Vico

Radiating crystal aggregates grow outwards from a central point They consist of multiple crystals growing in diverging directions Mineral examples wavellite pyrite rutile and kyanite The photo above shows a massive aggregate of kyanite crystals many of which form radial clusters The specimen is approximately five centimeters across

Sep 05 2019 · Previously it has been suggested that aggregates form during growth processes such as heterogeneous nucleation where a new crystal nucleates on the surface of an existing crystal dendritic growth which occurs when crystals grow extremely fast forming fingerlike dendrites this comes from the greek for ‘tree’ or twinning where two

Aggregates develop when primary particles begin to form a common crystalline structure From a physicochemical point of view the formation of aggregates corresponds to a sintering process like the formation of compact ceramic solids from several smaller primary particles Aggregates are an assembly of primary particles that have grown

Aggregates are obtained from rocks which in turn are composed of minerals either a single mineral or a mixture of minerals A mineral is naturally occurring inorganic has an order internal arrangement of atoms and has a definite composition or range of compositions

Its soapy or greasy feel accounts for the name soapstone given to compact aggregates of talc and other rockforming minerals Dense aggregates of highpurity talc are called steatite Talc common silicate mineral that is distinguished from almost all other minerals by its extreme softness

The term crystal habit describes the favored growth pattern of the crystals of a mineral species Adjectives used to describe the habit of individual crystals are equant prismatic and tabular Aggregates of crystals may also be termed equant or prismatic while aggregates of thin flat tabular crystals may be bladed Thin sheets flakes or scales are termed foliated micaceous

form whereas at low agar concentrations treelike crystal aggregates similar to diffusionlimited aggregation DLA develop in the entire system At an intermediate agar concentration Liesegang band forms near the contact surface while treelike aggregates appear suddenly at some distance from the contact The influence of agar concentration

Precious Stones in Afghanistan Afghanistan has been blessed with a great variety of precious and semiprecious stones with 73 records of mines deposits occurrences and showings In fact some of the earliest records of mining anywhere in the world are from Afghanistan dating back over 6000 years

Crystal aggregate lapis lazuli from Afghanistan Construction aggregate a gravel pit in Germany Soil aggregate in Spain In the Earth sciences aggregate has three possible meanings Earth science or geoscience includes all fields of natural science related to the planet Earth

Mineral Mineral Crystal habit and crystal aggregation The external shape habit of welldeveloped crystals can be visually studied and classified according to the various crystal systems that span the 32 crystal classes The majority of crystal occurrences however are not part of wellformed single crystals but are found as crystals grown together in aggregates

The thin crystal aggregate that spans the cleft can crack at slightly different positions The specimen is from Kuar Valley in Afghanistan 10mm 1152x1006 126kb Very often they form aggregates of two or more crystals like these two parallel grown crystals

Sep 05 2019 · Previously it has been suggested that aggregates form during growth processes such as heterogeneous nucleation where a new crystal nucleates on the surface of an existing crystal dendritic growth which occurs when crystals grow extremely fast forming fingerlike dendrites this comes from the greek for ‘tree’ or twinning where two

Aggregates develop when primary particles begin to form a common crystalline structure From a physicochemical point of view the formation of aggregates corresponds to a sintering process like the formation of compact ceramic solids from several smaller primary particles Aggregates are an assembly of primary particles that have grown

There are basically two types single crystal forms and aggregate forms The single crystal terms are used to describe individual crystals and so terms like platy or prismatic are used Aggregate terms are for minerals whose crystals come in groups of at times literally thousands of crystals and form

The word “crystal” comes from the Greek “krystallos” meaning clear ice A crystal is defined as a solid material consisting of a threedimensional periodic ordering of atoms molecules or ions Crystals form by a process called crystallization that signifies a transition from chaos to perfection

Jan 07 2015 · To better understand how renal stones form in vitro the role of calcium phosphate on the process of calcium oxalate nucleation and crystal growth must be further investigated It is accepted that Ca–P phases play a critical role in the formation of large aggregate

An aggregate of ice crystals blizzard High winds low temperatures and blowing or falling snow Another name for the icecrystal process of rain formation fall streaks These form when snowflakes or icecrystals fall from high cirriform clouds hailstreak A deposit of hail in a long narrow band

Jade is the name shared by two different minerals calcium magnesium silicate Nephrite and sodium aluminium silicate Jadeite Although their compositions crystal structures and densities are different they are both similar in looks and toughness and they

Crystal aggregates deposited in the kidneys can form urate renal stones and lead to renal failure In classic gouty arthritis monosodium urate crystals form and are deposited in joints and their surrounding tissues initiating a powerful inflammatory response Pseudogout is caused by the formation of calcium pyrophosphatedihydrate crystals The effect of either crystal is the same the

Aug 14 2020 · Contributor At times crystals will not form even when a solution is supersaturated as there is a kinetic barrier to crystal formation At times crystallization may need to be initiated for example if the solution becomes faintly cloudy as it cools or if the solution fails to produce crystals even when it is noticeably cooler than originally

Quartz is one of the Earths most abundant minerals It has a simple chemical formula SiO2 but is very stable and resistant retaining its identity even billions of years after its formation extreme weathering and transport Quartz Figperiod 1 has always played a large role in human technology