I can't really foresee a trading halt occurring regarding the upcoming assay results. However, to answer your question...
Trading halts occur when "a listed entity has become aware of information that a reasonable person would expect to have a material effect on the price or value of its securities but it is not in a position to make an announcement about the information to the market promptly and without delay."
Example 1: entity A, whose principal asset is a mine in a remote region, has just learnt that its mine has been hit by a major earthquake. Early reports indicate that the damage is significant. A intends to fly a team of experts to the mine to assess the damage but it is likely to take 48 hours for them to reach the mine and report back to A and then for A to prepare an appropriate announcement to the market about the extent of the damage and its likely impact on A’s operations.
It would be appropriate for A at that point to request a trading halt pending that announcement. The request for the trading halt, which would be released to the market, should mention that A’s mine has been significantly damaged by the earthquake, that A is sending a team to assess the damage and that a further announcement about the damage is anticipated within 48 hours.
In this case, ASX would likely grant a trading halt that covers the 48 hour period A says it needs to assess the damage and make an announcement to the market.
