* Crystallization speed depends on many factors:

* Temperature: Warmer solutions tend to crystallize faster, but there's a limit.

* Solution Concentration: A more concentrated solution means more dissolved material available to form crystals, potentially leading to faster growth.

* Impurities: The presence of impurities can interfere with crystal formation.

* Nucleation Sites: The presence of surfaces for crystals to start forming on (like a string, rough surface, or dust particles) can influence speed.

* Agitation: Stirring or moving the solution can disrupt crystal growth.

* Borax vs. Salt: While borax is known to form crystals readily, it doesn't necessarily mean it's always faster than salt.

To get a definitive answer, you'd need to compare them under controlled conditions, keeping all other factors constant.

In a general sense:

* Borax crystals are often larger and more aesthetically pleasing: This might suggest they grow at a slightly slower rate, allowing time for larger, more well-defined crystals to form.

* Salt crystals can form quickly: Salt is very soluble and readily forms crystals. However, they might be smaller and less visually interesting.

For a fair comparison, try this experiment:

1. Prepare identical solutions: Use the same amount of water and equal concentrations of borax and salt.

2. Keep everything else constant: Use the same temperature, container, and agitation level.

3. Observe the crystallization process: Note when the first visible crystals appear and how quickly they grow.

This experiment will give you a more reliable answer about which crystal forms faster under specific conditions.