Two bronze chien basins were studied to reconstruct replication techniques of late Chou founders. Ancient foundry techniques are reviewed. Both chien were examined by microscopy, radiography, chemical analysis and UV illumination to reveal condition and method of manufacture. Mold marks, casting remnants, chaplets, handles, decor and inscriptions are compared. The decor is modular; six basic motifs are repeated to produce the total design. However, two separate but similar vessel molds were constructed for casting the two vessels. Excavations at Hou-ma, where both chien may have been fabricated, provide information as to how appendages and decor motifs were replicated.