This was found in a study done by researchers of the Nueva Viscaya State University (NVSU) in Bayombong, Nueva Vizcaya.
Indigenous or recycled shells such as those of golden apple snail (golden kuhol) and mussel (tahong) could be used for tile-making, according to Dr. Felizardo P. Ubando and Rosalinda G. Nones in their research project titled "Powerred Shells as Tiles".
The study was monitored by the Los Baños-cased Department of Science and Technology-Philippine Council for Aquatic and Marine Research and Development (DOST-PCAMRD). Currently headed by Executive Director Rafael D. Guerrero III, PCAMRD is DOST's planning council for fisheries and aquatic resources that coordinates the national aquatic resources research and development network (NARRDN) now composed of more than a hundred R&D agencies and institutions.
In their study, Ubando and Nones followed processing steps such as washing and cleaning the shells, boiling to remove the impurities, air-drying, pounding and pulverizing, molding, drying, and impact testing.
The tiles produced were dried for 15 to 25 days.
As reported by PCAMRD's Dr. Dolly DG Fernandez, the ground shells mixed with styrofoam resulted in grayish tiles similar to the granite tiles, has similar texture, and were stronger and cheaper than the commercial tiles.
A piece of commercial tile costs P10 while th shell tile fetches a price of only P4.10 per unit, said Dr. Fernandez.
Findings of the NVSU study also showed that the shells are sources of calcium oxide (CaO), which strengthens the plastic materials of the experimental tile.
To be commercially competitive, however, the experimental tiles should further be tested to determine its endurance to weight or pressure and should be properly glazed, Ubando and Nones recommended. — Rudy A. Fernandez