I have a 1/4 lb bag of Yin Hao from Holy Mountain. After several
trials, I think I like it best at about 2.0-2.6 g/cup (6 oz) brewed at
160°-180°F for 1.5 to 3.0 minutes.

With those parameters, it is smooth and mild.

It has two characteristics I cannot identify.

1. Almost from the first sip, it feels like there is a slight coating
on the inside of my mouth. It's not quite like butter or fat, but
similar. It lasts for an hour or so after drinking.

Can anyone explain what this is?

2. After 2-3 cups, there is a slight after taste that I can't quite
identify. This tea has some jasmine and this after taste has a floral
character, so maybe that's it.

Can anyone help me here?