This time I would like to talk about the precautions to take when caring for antique cutlery (forks, knives, etc.).

After using antique cutlery for a meal or other occasion, wash it with a mild detergent and a soft sponge, then wipe off any moisture thoroughly with a cloth.
When doing so, do not use a dishwasher, dryer, or boiling water.

This is because the handle and blade of antique cutlery are separate parts, and they are often glued together using a material called "nikawa" (glue) which is made from animal collagen.

Glue has great strength when dry, but is weak when it comes to moisture and will melt if the temperature rises above 50 degrees.
If you use a dishwasher or dryer to wash the cutlery, it will get too hot, causing the paste to melt and spill out, making the cutlery look dirty and, in the worst case, unusable.

Also, there are methods for removing stains (black spots) from silverware that use hot water, aluminum foil, and baking soda (or salt), but you should never use this on cutlery where the handle and blade are separate parts.

Here's a photo of when I accidentally put some antique cutlery in boiling water a long time ago, when I didn't know much about such things.

If this happens, you will have to hire a professional to repair it, which will cost a fair amount.

In addition, using a dishwasher or other machine can cause the dishes to rub against each other, which can cause fine scratches on the soft pure silver, and in the case of silver-plated dishes, can cause the plating to peel off.
Boiling water is not a problem for cutlery such as spoons, which have a handle and bowl that are integrated, but it is still better to wash them by hand to prevent scratches.

If you wash it by hand, you don't need to be as careful about antiques as you would with modern tableware, but please be careful not to use a dishwasher or water over 50 degrees.

In addition to cutlery, you should also avoid using hot water to clean silver products such as teapots that have wooden handles or are lined with cloth or leather, or that contain parts other than metals such as silver or iron.