"I haven't read the 'other' companies announcements, but the...

"I haven't read the 'other' companies announcements, but the dive seems to have correlated with the scoping study results? Was it that, in combination with weaker markets?"

The release of the scoping study results kept the sp at even on a very bleak market day when mid cap and large cap gold producers were dropping 6-10%.
It "played catch-up" over the next few days when the all ords collapsed so much more likely market related than scoping study. The scoping study was very positive and near in line with my fairly bullish expectations for very low cap and cash costs.

Murchison did come in much higher than expected on cash costs and KGL dropped around 8% on a fairly neutral market day so that drop clearly was related to the scoping study.
Fortunately since then, drilling has identified high grade zones within first year pits which should bring cash costs lower for stage1 and continuing work has shown potential for some of the low grade ore to be dump leached decreasing likely cash costs for stage 2 from what they would have been using heap leach only.