Yorkie:
The ultra long, fine, silky coat parts along the spine and falls straight down on either side. It is steal blue on the body and tail, and tan elsewhere. Puppies are usually black & tan. The tail is usually docked to half its length. If the dogs are not for showing, the owners usually go for the shaggy look. The Yorkie has a flat head, medium-sized length muzzle, a black nose, and regular teeth. The eyes are extremely vivacious and the ears are v-shaped, erect or semi-erect. The tail is docked to medium-length and is carried level with its back. Its limbs are straight with round feet and black nails. The hair on the head is so abundant that it is almost always necessary to gather it in a band to keep from going into the dog's food bowl and to give the animal maximum visibility. Some owners choose to trim the hair on top of the head.
The breed is only 100 years old or so, but its origins are not entirely certain - probably because the working men of north England, who developed the Yorkshire Terrier for catching the terrible rats that infested the mine shafts and as a hunting dog that could penetrate into badger and fox burrows, avoided divulging the secret of their success to those who might have cashed in on a lucrative side line. However, it seems likely that Scotsmen seeking work in the woolen mills of Yorkshire brought with them various types of terrier, including the Skye and the now extinct Clydesdale. These were then crossed with local types, such as the long- haired Leeds Terrier. The Maltese, Black & Tan Manchester, and Dandie Dinmont Terriers may also have contributed blood lines. At first, the Yorkie was a much bigger animal than the one we see today, but by selectively breeding the smallest individuals, the dog was gradually miniaturized over the years. They were made into a fashion dog. Women carried these little dogs in their bags and under their arms. The first Yorkshire, with the characteristics demanded by its standard today, appeared in a dog show in 1870.
In 1984 a piebald Yorkie was born as a result of a genetic recessive gene occurrence from 2 Yorkshire Terriers. Today the piebald dogs are considered a different breed; which is named the Biewer or Biewer Yorkie.
Height: 6-7 inches (15-17½cm.)
Weight: 7 pounds (3.2kg.)
Silky:
The Silky Terrier, also called the Sidney Terrier, is a fine-boned, moderately low-set, long-haired terrier. It is compact but lightly built. It has erect, v-shaped ears and a docked tail. (Docking is illegal in some European Countries.) The head is flat and wide between the ears, with a shallow stop. The nose is black and the eyes are round and dark with a piercing expression. The teeth should form a scissors bite with a sturdy jaw. The body is slightly longer than tall with a level topline. The round, catlike feet are small and well-padded. Dewclaws should be removed. The coat is long, about 5-6 inches (12-15 cm). The fine, silky, shiny hair has no undercoat. It is very prone to tangles and mats unless frequently groomed. The coat should not reach the floor. The hair is parted down the center of the back. The coat comes in blue & fire red, or blue with tan markings. Many shades of blue are permitted. The topknot should be lighter in color than the tan points. Silky Terriers are born black.
The Silky Terrier was originally developed in 19th century Australia from other terrier breeds such as the Skye and Cairn but primarily the Australian Terrier and the Yorkshire Terrier. American servicemen stationed in Australia during World War II brought Silky Terriers home with them after the war. The breed was recognized by the AKC in 1959 and its standard was established in 1962 (and later updated in 1967). Though the Silky Terrier has always been primarily a companion dog, this swift little dog can catch domestic rodents.
Height: 9-10 inches (23-25 cm.)
Females are generally smaller than the males.
Weight: 8-11 pounds (4-5 kg.)
Source(s): http://dogbreedinfo.com/yorkshireterrier... http://dogbreedinfo.com/silkyterrier.htm