Varying [Ca 2+] and [C2O42 – ] changes the CaOx
crystals and the CaOx-modifier crystals reaction, leading to morphological variation of CaOx crystals 6.
At higher values of [Ca 2+] and [C2O42 – ], the COM
particles were dendritic rather than hexagonal in shape
(Fig. 3a) as was also shown in Refs. 5, 22. The
amount of COD particles of octahedral shape gradually increased with small caltrops concentration. The
compositions of crystals in the higher concentration
case were also characterized by EDS. The chemical
elements were found to be in the same ratio as for the
lower concentration case.