An ice auger only has a limited reach Fish so making it all the way down to bedrock in many areas isn't going to happen. If you do decide to give it a try, take a 4'x4' section of ply and cut a hole a couple of inches larger than the diameter of the bit in the center. Then place it over your drill location. As the dirt comes out it will go onto the ply instead of the surrounding ground. Makes accurate testing much easier.
Drill testing can show you several things. Besides the amount of gold in an area it can show you the profile of the bedrock. Know this can help you to decide exacty what kind of gear is going to be needed to work the claim in the most economical method. Testing is an important process in proving a claim out here. If you don't test and prove that there's good gold on the claim, then if for some reason they kick you off it you'll have data to show when you file a taking suit against the agency. No data=No cash award.