The diagrams below show two cutting tools made from stone. They are from an early period and a later period of human history. The tools were made by breaking off small pieces of stone.

The diagrams illustrate a pair of stone cutting implements, namely

tool

A and

tool

B

, which find their origins in two differing periods of human history. They were crafted through the technique of chipping away small fragments of stone.

Overall

, there were noticeable differences between the two tools, with the one from 0.8 million years ago having greater dimensions, less rugged surfaces, and more uniform edges in comparison with its earlier counterpart. Looking first at

tool

A, which dates back to 1.4 million years ago, it appears to be highly primitive.

This

artifact

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artefact

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measures approximately 7

centimeters

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centimetres

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in height and 3

centimeters

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in width, and its thickness falls within the range of 2 to 3

centimeters

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. Similar to the later version,

tool

A features a rounded base, tapering toward the top. The latter,

however

, has much rougher surfaces when viewed from the front and the back,

thus

contributing to its more jagged edges and a less defined pointed end.

Tool

B

,

on the other hand

, shows a more refined appearance, resembling a teardrop, as its tip is notably sharper

while

the sides are

also

smoother.

In contrast

to

tool

A, the front and back of

tool

B

look somewhat similar, with less surface roughness.

Furthermore

,

Tool

B

is about 5

centimeters

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longer and 2

centimeters

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wider than its predecessor,

although

the thickness is almost exactly the same.