Is most stoneware (ironstone) microwave safe?

Most stoneware is not microwave safe, although some exceptions exist. True ironstone is microwave-safe, but most dinnerware labeled "ironstone" in modern times is actually stoneware, which is not. Stoneware is a type of ceramic made from a non-porous clay that is fired at a high temperature. This makes it durable and strong, but also means that it can become very hot when microwaved, potentially causing damage to the dish or the microwave itself. Additionally, the metal oxides used to give stoneware its color can leach into food when microwaved, posing a potential health risk.

True ironstone, also known as transferware, was produced primarily in England in the 1800s. It is made from a mixture of clay and iron oxide and is fired at a high temperature, making it strong and durable. Unlike stoneware, ironstone is microwave safe. However, it is important to note that some older pieces of ironstone may contain lead, so it is always best to check the manufacturer's instructions before using it in the microwave.

Some stoneware manufacturers produce microwave-safe products and may label them as such. In general, it is important to check the product label or manufacturer's instructions to determine whether a specific stoneware item is microwave safe before using it.