A friend of mine has Sheffield strawberries 'n cream stoneware plates. On bottom it says "oven to table", "Microwave oven safe", and "Dishwasher safe". All I did was place a bowl of soup on one, and it made loud noise and a crack appeared.

Hi. That is by a different Sheffield. Our pottery was hand made in Sheffield MA from 1946 until about 1980 and has a totally different look to it. There are actually several companies that made pottery under the name Sheffield; mostly in Sheffield England where pottery has been made for centuries. I see that Sheffield Strawberries n cream was mass produced in Japan. I don't know if that company still exists. I see a lot of that pattern is available on ebay super cheap so you should be able to find yourself a replacement fairly easily for something like $10! https://www.ebay.com/itm/Lot-3-Vintage-Sheffield-Strawberries-n-Cream-Plates-2-Appetizer-Dessert-1-Dinner/133513756603?hash=item1f160a3fbb:g:-EMAAOSwDJZfSoej and here is an example of what our stuff looked like if you're interested https://www.ebay.com/itm/Vintage-Sheffield-Pottery-Massachusetts-Flower-Vase-Planter-Floral-Dogwood/402246605710?hash=item5da7c41b8e:g:Pu0AAOSwBY5dvNUD

The crack on the strawberries n' cream plate is half way across and all the way through. It can not be used now. How do I get it replaced? It is a defect in plate.