The first phase of the Indian Mesolithic period dates back to the era between 10,000+ BC and c. 5,000-4,000 BC. There is some consistency in this spread of dates in Rajasthan, Madhya Pradesh, Uttar Pradesh and Bihar. There are also many late dates from other apparently Mesolithic contexts. For instance, the Lekhahia rock-shelter in the eastern Vindhyas has three seventeenth century AD dates from the phase 4 of its Mesolithic occupation. Either these dates are based on contaminated samples or indicative of a very late con-tinuation of the use of microlithic tools in this area.
In addition to the 'pigmy' versions of the upper Paleolithic types, such as points, scrapers, burins, awls, etc., there are lunates or crescents and the so-called geometric shapes of rhomboids, trapezes and trapezoids, and triangles. The presence or absence of the geometric shapes establishes the status of a particular microlithic industry as geometric or non-geometric. As far as the presently available evidence goes, the latter may be earlier than the former in a particular sequence, but geometric type by itself need not be taken as indicative of a late assemblage. In both cases, the tools are too small to be effective as single specimens, although excep-tion may be made in the case of those which could be used as arrowheads and drill-points. They were mostly hafted into handles of wood or bone and formed composite implements, such as saws, sickles, etc. Actual speci-mens of such implements made by hafting microliths in a handle have been found in suitably preserved archaeological situations.
That the Indian microlithic industry is rooted in the preceding phase of upper Paleolithic industries is proved both by the continuation of the archaeological stratigraphy from the upper Paleolithic into the microlithic and the development of the latter category of tools from the former category. The element of stratigraphic continuity is clear from ailed areas and localities where a full prehistoric profile from the Paleolithic to the Mesolithic is available. The continuity of lithic technology is apparent too, wherever a close study of the lithic assemblages of both the upper Paleolithic and the Mesolithic has been made. Patne in the Chalisgaon area of Maharashtra is an excavated site where such a study has been made. The presence of backed, pen-knife and truncated varieties of blades along with lunates, triangles and trapezes in this level clearly foreshadows the development of the full-fledged microlithic industry of the succeeding phase. As per the study of the excavation, it has been noted that the 'Microlithic character obtained in the Late Upper Paleolithic'.
Moreover, it has been noted that the Chopani Mando, contains an industry of backed blades, parallel-sided blades, burins, points, scrapers, cores, flakes and blanks which are smaller than the same type of upper Paleolithic artifacts but longer, thicker and broader than the true Mesolithic artifacts. In the Belan valley the emergence of microliths towards the end Pleisto-cene is a clear possibility. In certain areas, however, the use of microliths could have continued till the early medieval context. The early historic level of Dihar in Bankura, West Bengal, supposedly contains microliths made of bottle glass and in the same region lithic spe-cimens have been found in association with c. tenth to twelfth century AD pottery. The tradition of making microliths out of bottle glass has been documented in the Andaman Islands in the nineteenth century. In fact, un-dated microlithic contexts in India do not denote a Mesolithic phase. Myri-ads of surface clusters of microliths in the subcontinent are undated and thus cannot be put in a specifically Mesolithic context.
Although the distribution of early, truly Mesolithic evidence in India is still limited, the distribution of microlithic sites is not; in fact, it is easier to note the areas without microliths than those with them. Except in a limited section of the Ganga plain, i.e. part of a strip between Pratapgarh and Banaras, microliths are not yet known to occur elsewhere in the Indo-Gangetic plain. The hilly areas of the north-east too have not yet revealed any categorical proof of the existence of this industry. Otherwise, microliths are more ubiquitous than Palaeoliths in the sense that they are far more visible in the landscape. The modern population explosion has, however, destroyed many microlithic clusters in many areas of the subcontinent.