A simple freeze-fracturing and etching apparatus using the cold block principle.

An inexpensive freeze-fracturing and etching equipment, based on the cold block principle, is described. The specimen is fractured inside the apparatus before replication with the aid of a simple fracturing device. The cleavage plane can be preselected and complementary fracture surfaces of tissue blocks are easily obtained. Since fracturing is carried out without the use of knife, large areas can be studied on the replica which is free of knife marks. Temperature measurement and heating of the lower block makes controlled etching possible. The apparatus can be constructed in a laboratory workshop at very reasonable expense; the results have been comparable to those obtained with most good quality or sophisticated freeze-etching equipments.