The objective of this study was to extract and concentrate calcium oxalate
(CaOx) crystals from plant leaves that form the above mentioned crystals. The
chemical and physical studies of CaOx from plant to be performed depend on an
adequate amount of the crystals. The plant used in this study was croton (Codiaeum
variegatum). The leaves were ground in a heavy duty blender and sieved through
a 0.20 mm sieve. The suspension obtained was suspended in distilled water. The
crystals were concentrated at the bottom of a test tube. The supernatant must be
washed until it is free of plant pigments and other organic substances. Biogenic
CaOx crystals have well-defined and sharp peaks, indicating very high crystallinity.
Moreover, the CaOx crystals were not damaged during the extraction procedure,
as can be seen on the scanning electron microscope images. The porposed method
can be considered efficient to extract and concentrate biogenic calcium oxalate.