Which of the following attributes were not common of indus valley stamp seals? a. the stamps were carved out pure limestone. b. they were used as marks of ownership/status. c. they were often engraved with animals, humans, fantastic creatures, or divinities. d. the stamps contain inscriptions along the top edge.

The answer is option a, that is "The stamps were carved out pure limestone".
This sentence is false because the stamps were actually made of another kind of rock such as  stearite which is a magnesium-rich rock composed of mineral talc and some of them are also made of silver or calcite.

These traits are all equally important in recognizing the validity of artwork mainly due to an artists' consistent style and reputation which they have developed over a lengthy period of time. most famous paintings contain specific characteristics of the artist who created it. an appraiser would pay close attention to certain key elements within the painting, as well as an accuracy in measurement and color shade. blended textures and outlines are essential in recognizing an authentic piece from a copy. signature and imagery exist in epic proportions to balance out each trait as they coexist in harmony, depending on preference and style of each artist. no two original pieces are virtually identical, although it may be almost impossible to see discrepancy with the naked eye.

It increased the value of original works of art.