A picture would be a great help.
Particularly of the back stamp. Is it in black? Green? Incised? is there an incised number? any figure?
Need to know more.

You may have a very old piece of English Herculaneum pottery. Some of their marks are simply the name in upper case stamped on the back......and if the mark is slightly illegible, the EUM in upper case may appear to be P or F-U-V. If this is the case, it would date early 1800s and no later than 1830.

camera is not working so I cant send picture, name is stamped into platter.. uppercase, black, no other markings, no figures or numbers...the last three letters are slightly illegible so maybe they are actually EUM...that would make it almost 200 yrs old....wow...Im so excited...thank u,this is a strong possibility...and Uncle Porter's home was an old, old home...

I think it's not only possible, but very probable this is what you have. Herculaneum was not actually one factory but a group underwhich several potteries sold their wares through a central point in Liverpool. It has been noted the backstamps on many were 'light' and most all Herculaneum is marked. The plain stamp is indicative it is an earlier piece before 1810, and yes they did make platters.

Herculaneum is a popular collectible in the U.K., though many (perhaps most) of their wares were exported. There are some very good books with Herculaneum history but not in general circulation. Is the bottom glazed? What condition is your piece in?

Platter has been well used, has scratches and some tiny dark/brownish dots, bottom is glazed. it sat on shelf for many years, must have gotten dirty and dusty...i wonder if it would cleanup better..i have only used dish soap and water. 2" wide rim with some scallopping, no cracks, chips. One of the scratches on the bottom I thought could be a crack but doesnt go thru to top so i dont think it is. I wish camera worked so i could send a picture. I appreciate your help and input. I did read some on the Herculaneum mark and pottery a few minutes ago. (would have read it earlier but I HAD TO WORK)I also wondered if the black I see on letters is dirt.... again, thanks

Don't do anything major with it as far as cleaning right now other than to dust it. Treat it very gently until you can get someone to actually look at it to verify it is Herculaneum and get a value on it. The dots are normal for its age. Scratches are expected too on pottery that old put to household use.

I have no idea where to go or who to contact to verify/appraise it. We live near IU (Bloomington, IN) and 90 min from Indianapolis.

I think the chances of it NOT being early herculaneum are pretty slim, given your description....so assume it is!
Borrow or buy a camera and get some pictures and search the web for someone who either is selling or buying such old ironstone and email them a picture and ask if they know where you can get more information.
Linda C