Theory:

Mesolithic Culture in Tamil Nadu
Having not much evidence of Upper Palaeolithic Culture found in Tamil Nadu, Mesolithic culture prior to the Neolithic can be seen in many parts. The proofs can be seen at Chennai, North Arcot, Dharmapuri, Salem, Coimbatore, Ariyalur, Tiruchirappalli, Pudukkottai, Madurai, Sivagangai, Tirunelveli and Kanyakumari. People who lived in parts of Athirampakkam and Gudiyam Cave used microliths(very small geometric-form tools commonly fixed in the tip of spear, arrows and other hunting tools) or small-stone artefacts. Flint is a type of quartz stone which was used to rub and make fire. Chertis a silicon dioxide rock and its small sharp parts used in making composite tools, they used it for hunting, to cut the animals, to pierce the wooden and animal skins. The main occupation of the people were hunting, gathering fruits, nuts and roots.
 
Scrapers are tools used for scraping the surfaces. Like side scraper, round scraper and end scraper have various styles of usage on cutting and shaping of the rock stone and converting them to the final tool. Triangles as the name reveals that the tools are triangular in shape, and used as projecting edges fixed in the harpoons for hunting whales.
Lunates are in crescent shape .They were used as compound tools after mounting to a handle.
 
screenshot_03microliths.jpg
Microliths
 
Microlith_in_hand.jpg
Scraper tool
 
Articles  found at Chennai, North Arcot, Dharmapuri, Salem, Coimbatore, Ariyalur, Tiruchirappalli, Pudukkottai, Madurai, Sivagangai, Tirunelveli and Kanyakumari  of Tamil Nadu, are shows the Evidence of Mesolithic hunter-gatherers existence. The red sand dunes “teris” artefacts findings near Thoothukudi have been considered to be from the microlithic age.
Neolithic Culture in Tamil Nadu
The New Stone Age is the age during which human civilisation has started blooming. Domesticated animals and cultivated crops have been seen during this age in Tamil Nadu. Unlike earlier stone ages, the Neolithic people used polished tools. Stone axes which are also known as Celts are used for various works. Cattle growing was their main occupation. They lived in small settlements with dwellings made of thatched roof and clay plastered walls. Proof of Neolithic period village is found at Payyampalli in Vellore district and a few sites in the Dharmapuri region.
 
Payyampalli, a village in Vellore district of Tamil Nadu, seems to be a very important place, from where notable use of pottery, domestication of crops like horse gram and green gram were evident. Most of the Neolithic period activities are widely found in this site. Neolithic people possibly devised a slow wheel called turn-table and made the first pottery out of hand. In The process of burning, before firing, the pottery was polished with pebbles.
Reference:
https://rogergrace.webmate.me/SARC/type/microliths_files/screenshot_03microliths.jpg
https://en.wikipedia.org/wiki/Microlith#/media/File:Microlith_in_hand.jpg