The research campaign on the flint mining site of Cruci, in the territory of Peschici, produced interesting results with regard to the understanding of the working of raw materials close to the mining area.

The work concentrated on one of the most extensive spreads of worked flint (CR4), present in the area of Cruci, situated on the upper part of the slope at whose base mines 1 and 2 lie, the latter investigated at the beginning of the 1930s by Ugo Rellini. The area, on which a substantial quantity of worked flint appears, covers about 250 m2 and is at present an olive grove. In the past implements of various types have been found here, including mining tools but mainly burins (over 1000). This is an exceptional quantity for any surface site, and in particular for an Eneolithic workshop connected with mining activity. It was decided to put in a series of trenches in order to identify the horizon from which this material came.

A first trench (2) in the lower part of the area, where the amount of worked flint on the surface was the most abundant, unfortunately produced a negative result. The bedrock appeared below only about 20 cm of surface soil mixed with gravel and worked siliceous material, certainly in secondary deposition. The material had certainly slipped downwards, indicating that its primary deposit must have been higher up the slope.

Following a re-examination of the surface concentrations of material and their typology, a second trench (3) was opened in the highest part of the scatter, where a large amount of flakes resulting from actual débitage appeared. The excavation (1 × 1 m) was situated at about 20 m from the smallest entrance to mine no. 2 and produced a different stratigraphy from that documented in trench 2. A very recent surface layer of about 10 cm (US 1) was constituted by light brown soil and gravel with very abundant retouched and non-retouched lithic industry, including numerous burins. Below was a second layer, about 15 cm deep, removed as two sub-units (US 1A and US 1B), with the same sedimentological characteristics and abundant lithic industry, above all in US 1 A, less abundant in US 1B. Some of the artefacts presented lime concretions on the surfaces, probably the result of the original contact with gravel from the mine.

Like US 1, this second layer is to be considered in secondary deposit, probably not recent, formed by material from a deep archaeological level, situated a little higher up the slope.

This hypothesis appeared to be confirmed by the levels underlying US 1: a layer of completely sterile, white limestone mine gravel (US 2), about 20 cm deep, overlying a layer of brown soil (US 3) with lithic industry emerging at the roof. Unfortunately, the excavation stopped here.
The material present throughout US 1 probably came from this level which continued uphill from the trench and whose formation probably occurred over a long time period.
The extension of the trench uphill may confirm this hypothesis.

In the area surrounding the trench, still within scatter CR4, numerous implements were collected, in particular over 50 burins, confirming what was documented by earlier research.