Persian lamb fur , Swakara , Ashtrakhan , Broadtail are words that often create confusion to someone interested in acquring them. So... here's some information that might help sort things out a bit

Swakara stands for south west africa karakul . Karakul is a turkish word for black sheep. Swakara is a brand name and not a category of fur. Originally European settlers brought to Namimbia special sheep that were farmed for their skins. Nowadays swakara skins are world renonwned for their high quality standards.
Astrakhan is another brand name , referring to sheep farmed in the omonymous russian area near the Volga river.
Persian lamb fur is the name used in the west most commonly to describe the furskins coming of recently born or unborn lambs.
Broadtail is a term used to describe fur skins coming from unborn lambs and is the highest valued type of lamb fur.
Persian lamb has been considered as a finesse fur , a garment for aristocracy . It inspires class without being ostentatious and it manafes to turn heads without crying out loud. It is dressy and has a formal nature.
A few decades persian lamb fur coats were heavy and rather stiff. Nowadays the tanning process has evolved and skins are soft and more lightweight.
One importnat factor that determines , price is the look of the fur. Skins coming from unborn lambs have a glossy , flat , wavy "moiree'" look that is highly apraised and literally loved by haute couture designers. Skins from lambs aged 1-10 days start to grow hair that tend to look like the grown lambs as we know them. The hair is longer and curlier. Below are photos where the differences are portrayed.

Broadtail Lamb Fur Coat- Highly valued

black broadtail knee length fur coat

 Broadtail Fur Coat

black broadtail knee length fur coat

Standard Quality Persian Lamb Fur Coat
medium value black persian lamb fur coat
Basic Quality Of  Persian Lamb Fur
curly and robust lamb fur coat made of fullskins
Apart from lamb coats that are made of full skins you can find coats made of sections. Their making is a whole art itself , demanding and has its roots in Greece , where the majority of them are made by artisans . Experience , knohow , sharp eyes and skillfull hands produce stunning results. 
Either the paws or the dorsal area is used. 
Persian lamb fur coats made of paws are the most valued ones. They have a glossy look and wavy pattern , -qualities found in broadtail . Dorsal area sectional fur coats are more sporty and ideal  for casual wear.
Black Paws Fur Plate
trapezoid black persian lamb paws fur plate
Cognac Lamb Plates Made of Paws and Dorsal area Side to Side
upper plate made of dorsal area sections - lower plate made of cognac colored paws