The correct option is 2 and 3 only.
Explanation
The Indus Valley Civilisation (Harappan Civilisation) is renowned for its sophisticated craft production, particularly its bead-making industry, which demonstrates advanced technological knowledge and aesthetic sensibility.
- Statement 1 is Incorrect: Bead-making factories were not exclusive to Mohenjodaro. Specialized centers for craft production, specifically bead-making, have been identified prominently at Chanhudaro and Lothal. Chanhudaro was almost exclusively devoted to craft production, including bead-making, shell-cutting, metal-working, seal-making, and weight-making.
- Statement 2 is Correct: Harappan craftsmen used a diverse range of materials to manufacture beads. These included stones such as carnelian (a distinct red stone), jasper, crystal, quartz, and steatite; metals like copper, bronze, and gold; and other materials like shell, faience, and terracotta.
- Statement 3 is Correct: The technology of bead-making was highly developed. Some beads were composite, made of two or more stones cemented together. Others featured caps of gold. The shapes varied widely, including disc-shaped, cylindrical, spherical, barrel-shaped, and segmented forms.
Key Takeaway: The Harappan bead industry was a specialized craft with dedicated production centers like Chanhudaro and Lothal, utilizing a wide variety of materials ranging from common steatite to precious stones like carnelian.