How an angora blanket traps heat
An angora wool blanket is a throw or bed layer woven from the long, downy coat of the angora rabbit, a fibre of roughly 10 microns that is about half the width of merino wool and about half the diameter of human hair. That micro-fine diameter lets the yarn hold a high percentage of trapped still air, and it is the trapped air, not the fibre alone, that holds body heat against the body. A single blanket in this class weighs 500 g to 900 g, which is 20 to 40 percent lighter than a comparable 1.2 kg wool duvet cover, yet it holds warmth across the same 4 hour night. The mechanism is the same one that powers the garments in this site, from the base layer to the angora jumper, so the page moves from the fibre to the finished blanket and then to the garments that share its heat logic.
Because the blanket and the garments in this library are cut from the same fine animal fibres, the heat they hold comes from one shared mechanism: still air, held in place by the fibre. The section "How thermal underwear works" applies that mechanism to the base layer against skin, and this page applies it to a 900 g throw across a mattress. The physics is identical; only the distance the air must travel changes. The two fibres doing the work are Angora and wool, and their sizes set the rest of the page.
What an angora wool blanket is
An angora wool blanket is a woven or knitted throw made from the long fibre of the angora rabbit, which grows 12 cm of new down each month and is sheared 2 times per year. The finished piece is typically 130 cm by 170 cm for a single bed and 150 cm by 200 cm for a double, and it reads as a 500 g to 900 g garment you drape rather than a heavy quilt you are buried in. Two fibre families supply it. Angora fibre averages 10 microns in diameter, merino wool averages 19 microns, and human hair averages 70 microns, so the rabbit fibre sits between the two ends of the comfort scale. When a blanket blends the two, the common ratio is 50 percent angora and 50 percent wool, which trades some loft for some pilling resistance.
Where the fibre comes from
The angora rabbit is a breed, not a wild animal, and the two main types are the English angora, which is smaller and carries a denser coat, and the giant angora, which yields more fibre per shearing. The fibre is combed or plucked, carded into a top, and spun into a yarn of 16 to 20 runs, a count thin enough to loft but strong enough to hold a 150 cm by 200 cm weave. A well-made blanket shows 10 to 12 stitches per inch in the knit face, and that stitch density is what keeps the air cells small enough to stay still.
How the fibre traps heat
The fibre traps heat by holding still air, and the amount of still air a blanket holds is set by its loft and its diameter. Warm air rises and cold air sinks in a convection current, so a blanket that lets the air move will lose that heat to the room. Angora's 10 micron fibre packs more loft per gram than merino's 19 micron fibre, so a 700 g angora blanket holds a thicker still-air layer than a 700 g merino blanket of the same size. That still-air layer is the insulating material, and the fibre is only the scaffold that keeps it from moving. A 1 cm layer of still air carries roughly the same insulating value as a 3 cm layer of a low-density foam, which is why a lofty blanket outperforms a dense one of equal weight.
Why the diameter matters
Diameter matters because it sets both the loft and the drape. Fibre below about 16 microns feels soft against skin and traps more air, while fibre above about 24 microns feels stiffer and packs less air. Angora at 10 microns and merino at 19 microns both sit in the soft zone, which is why they dominate the luxury category. The finer the fibre, the more of it a single gram of yarn can contain, and the more micro-cells it can form, so the 10 micron fibre wins on pure loft. The 19 micron fibre wins on durability, because its longer, stronger staple resists the felting that a 10 micron yarn will do after 10 to 15 washes.
Angora wool versus merino wool
Angora wool and merino wool differ in 4 measurable ways: diameter, loft, pilling resistance and drape. The table keeps the numbers side by side so the choice is a matter of which property you weight higher, not a matter of taste.
| Property | Angora (rabbit) | Merino (sheep) |
|---|---|---|
| Fibre diameter | 10 microns | 19 microns |
| Loft per 100 g of yarn | Higher | Moderate |
| Pilling after 5 washes | Noticeable | Low |
| Warmth at equal 700 g weight | Warmer | Lightly cooler |
| Drape | Soft, hangs | Body, holds shape |
| Typical price per 150 cm by 200 cm | 250 to 450 pounds | 120 to 220 pounds |
The blend that captures both sides is 50 percent angora and 50 percent wool, which gives you the loft of the rabbit and the pilling resistance of the sheep in a single 700 g blanket.
How a blanket compares to heated alternatives
A blanket is passive insulation, while a heated blanket is an active heater, and the two solve different parts of the cold problem. A heated blanket draws 75 W to 150 W from the wall to push warmth through the body, and it is the right tool when the room is 10 C and the body is already cold. A 700 g angora blanket draws 0 W and instead holds the body's own 37 C heat against the skin, which is the right tool when the room is 15 C and the body is warm. The phrase "Thermal underwear heated" names the active version of the same logic applied to the base layer, where the heated panel is sewn into the garment rather than the blanket. The choice between the two comes down to the starting temperature of the body and the room, not to the quality of the fibre.
Which cold each fibre wins in
Each fibre wins in a different band of cold, and the band is set by the loft and the diameter. In a room at 15 C to 18 C, the 10 micron angora blanket wins, because its loft holds enough still air to keep a warm body comfortable without overheating it. In a room at 10 C to 14 C, the 19 micron merino layer wins, because its denser pack holds the heat of a cold body better than a lofty angora throw that lets too much of it escape. Below 10 C, neither single fibre is enough, and the correct build is a 2 layer system: a 250 g merino base against the body and a 700 g angora throw over it, which puts the dense pack where the heat is made and the lofty pack where the heat is held. The warmth inside an angora jumper is the same 2 layer principle worn against the skin, with the 10 micron fibre doing the holding and the wool doing the structure.
How a 700 g angora blanket is made
A 700 g angora blanket is made in 5 steps, and each step sets a number that shows up in the finished piece. The fibre is sheared and combed into a top, the top is spun into a 16 run yarn, the yarn is knitted at 10 to 12 stitches per inch, the knit is washed and fulled to 150 cm by 200 cm, and the finished piece is trimmed and weighted at 700 g. The 16 run count and the 11 stitch face density are the two numbers that decide the loft, and a change of 1 stitch per inch shifts the final weight by about 60 g. The finished blanket should feel soft to the wrist, hold its 150 cm by 200 cm shape off the bed, and trap enough still air to hold a warm body comfortable in a 15 C room.