What is not a characteristic of acceptable sand for the sand cone method?

The presence of organic materials is not a characteristic of acceptable sand for the sand cone method because organic materials can decompose and change in volume, leading to inaccurate density measurement results. The sand used in this testing method must provide consistency and reliability, which organic materials cannot assure due to their variability and potential for breaking down over time.

In contrast, acceptable sand should exhibit consistent bulk density, meaning its density remains stable across the different sample volumes. Being free of fine particles is essential as these can fill voids in the coarse sand, affecting the accuracy of volume measurements. Uniformly graded sand helps ensure that the voids between sand particles are consistent, which is vital for achieving accurate results when determining the density of soil.