The boyar hat was a fur

Fur

Fur is a synonym for hair, used more in reference to non-human animals, usually mammals; particularly those with extensives body hair coverage. The term is sometimes used to refer to the body hair of an animal as a complete coat, also known as the "pelage". Fur is also used to refer to animal...

 hat worn by Russian nobility between the 15th and 17th centuries, most notably by boyar

Boyar

A boyar, or bolyar , was a member of the highest rank of the feudal Moscovian, Kievan Rus'ian, Bulgarian, Wallachian, and Moldavian aristocracies, second only to the ruling princes , from the 10th century through the 17th century....

s, for whom it was a sign of their social status. The higher hat indicated the higher status.
In average, it was one ell

Ell

An ell , is a unit of measurement, approximating the length of a man's arm.Several national forms existed, with different lengths, includingthe Scottish ell ,the Flemish ell ,the French ell...

 in height, having the form of a cylinder

Cylinder (geometry)

A cylinder is one of the most basic curvilinear geometric shapes, the surface formed by the points at a fixed distance from a given line segment, the axis of the cylinder. The solid enclosed by this surface and by two planes perpendicular to the axis is also called a cylinder...

 with more broad upper part, velvet

Velvet

Velvet is a type of woven tufted fabric in which the cut threads are evenly distributed,with a short dense pile, giving it a distinctive feel.The word 'velvety' is used as an adjective to mean -"smooth like velvet".-Composition:...

 or brocade

Brocade

Brocade is a class of richly decorative shuttle-woven fabrics, often made in colored silks and with or without gold and silver threads. The name, related to the same root as the word "broccoli," comes from Italian broccato meaning "embossed cloth," originally past participle of the verb broccare...

 top and the main body made of fox

Fox

Fox is a common name for many species of omnivorous mammals belonging to the Canidae family. Foxes are small to medium-sized canids , characterized by possessing a long narrow snout, and a bushy tail .Members of about 37 species are referred to as foxes, of which only 12 species actually belong to...

, marten

Marten

The martens constitute the genus Martes within the subfamily Mustelinae, in family Mustelidae.-Description:Martens are slender, agile animals, adapted to living in taigas, and are found in coniferous and northern deciduous forests across the northern hemisphere. They have bushy tails, and large...

 or sable

Sable

The sable is a species of marten which inhabits forest environments, primarily in Russia from the Ural Mountains throughout Siberia, in northern Mongolia and China and on Hokkaidō in Japan. Its range in the wild originally extended through European Russia to Poland and Scandinavia...

 fur.

When taken off, the hat was often held above the forearm, between hand and elbow

Elbow

The human elbow is the region surrounding the elbow-joint—the ginglymus or hinge joint in the middle of the arm. Three bones form the elbow joint: the humerus of the upper arm, and the paired radius and ulna of the forearm....

, or worn as a muff

Muff (handwarmer)

A muff is a fashion accessory for outdoors usually made of a cylinder of fur or fabric with both ends open for keeping the hands warm. It was introduced to women's fashion in the 16th century and was popular with both men and women in the 17th and 18th centuries. By the early 20th century muffs...

.

Today the hats of this type are sometimes used in the Russian fashion

Fashion

Fashion, a general term for a currently popular style or practice, especially in clothing, foot wear, or accessories. Fashion references to anything that is the current trend in look and dress up of a person...

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