Welcome to the technical forum. Do you have any additional information like what the part marking on the board is ? Does it have something like a D with a number? This would indicate that it is a diode. I am looking at this picture of 1N4148UR-1-ND. Though this one is 75 volts and only 200ma. Look at the picture and see if this is similar. I have a part number that is EGL34B-E3/98 that is 100 volts and 500ma. Though I wanted you to look at the first picture to see if this looks similar. The second one would be more to the specifications. If you could provide more information with dimensions we can sure check . Please review the part numbers provided to see if this looks like what you have .
It definitely looks like a jellybean small signal diode like @Verna_1353 suggests.
Are you sure that nearly 1/2A flows through that diode?
Usually circuits that pass more than a couple tenths of an amp use a diode in an epoxy package instead of glass for the better power handling.