Inquire about where the rug-makers crafted the rug or where the rug originates from. For example, if the rug is from any part of Asia, including Iran, China, India, Russia, Turkey, Pakistan, Tibet and Nepal, it is Oriental. If the rug is from Iran, the Caucasus, Georgia or Afghanistan, it's considered a Persian rug. If the rug bears a name after a specific city, such as Gabbeh, it's a Persian rug.
Examine the colors. If the colors are extremely bright, rich and brilliant, it's most likely a Persian rug, as that is a common trait of such carpets.
Ask the salesperson or vendor how many knots per square inch. An Oriental rug will have less than 160 knots per square inch and a Persian rug will have 160 or more, giving it a distinctive thickness.
Look at the patterns of the rugs. Persian rugs generally have delicate floral patterns with depictions of leaves and buds. Oriental rugs might have field designs such as a central medallion by itself or interconnected patterns coming outward from it. Alternatively, the design might have several compartments or display a scene.