Which of the following is NOT associated with the appearance of leucine crystals?

Leucine crystals are typically characterized by specific visual features that help in their identification during a microscopic examination of urine. They are known for their unique appearance, which includes radial striations, rosette formations, and concentric circles.

Radial striations create a star-like pattern indicative of leucine crystals, while rosette formations present as clusters resembling flower petals. Concentric circles, on the other hand, add to the distinctive visual appearance of these crystals by showing circular patterns.

Although leucine crystals can exhibit a range of colors, including yellow and brownish hues, the description of "substantial brown color" is not specifically associated with the typical appearance of leucine crystals. In fact, their most recognized feature is their yellowish color rather than a pronounced browning. Therefore, the option describing substantial brown color accurately reflects something that is not a distinguishing trait of leucine crystals.