p47y:

Star in a jar.

It emits light through any fabric and even through leather. Only metal can block its shine. Emits heat, but is bearable to the touch.

Upon breaking, a miniature star is released that illuminates a radius of 200ft like daylight. Any creature within 50ft of a released star will be blinded by its light and will suffer severe burns. The glass is thick and must be either smashed with great force or dropped from a high altitude.

concept and design: p47y

Do you think this is not well balanced? Any tips on making better homebrew items are greatly appreciated!