Hi - i wonder IF these might be considered to be (??) stoneware items. Funny thing with the Net, when your looking for something....if your typing Pottery if (might) just not come up....worth a shot
Also could you *dust* (or rub) them with some white powder (talc) to see if the marks come out better...
.....I am wondering on the Pottery Jug, is it a Creamer, or is it larger than that....and it *kinda* looks like the intials SV on the bottom --- but I am wondering IF those are squares around it, or just lines. As the lines (might) make the letter W (in a square shaped way) with the other letters S.V inside the (square-ish) W
Can't tell....if those lines might be also a letter, or blocks the SV is in....or is it SN
~ Might want to take a look around here for (Chinese Marks) for the first one....
http://gotheborg.com/