Identification: Unknown white mushrooms

Growing in a grass/thyme mix close to a big Pine tree. Smell pleasant, mushroomy. Could it be Amanita?

 

That is most likely Leucoagaricus naucinus, formerly known as Lepiota naucina. Check it out on MushroomExpert.com.

 

Yes, it fits photos and description. Thank you vitog.

 

any yellow staining on the stem with handling?

 

Don't remember any staining. Is it important?

 

Leucoagaricus naucinus tends to stain yellow when handled.

 

I checked it. No staining on the stem when touched. However they tend to became slightly yellowish after gathering, both stem and cap.