How can you tell if a Plus is supposed to be Beige or Platinum?

[olePigeon]

How can you tell if a Plus is supposed to be Beige or Platinum?  Is there a date range on the serial number, perhaps?

 

[sigtau]

Easy way: Open up the case, look for areas where it isn't coated in the ferric material but hasn't been exposed to sunlight, compare that color to the exterior.

Hard way: Probably a serial number, but FWIW, mine was one of the M0001A variants that did not list memory on the back (i.e. Macintosh Plus 1MB)--it just said "Macintosh Plus" and it was Platinum.

 

[chu-oh]

Easier way would just to look inside the battery clip.

 

[Scott Baret]

The brightness knob is another good indicator. They're a much more distinct brown on beige models.

There's also the base of the computer, which never really yellows since it's always sitting on a desk.

For serial numbers, if it was made in 1986, it's going to be beige. Some early 1987s may be beige as well, but from March 1987 onward, Pluses are platinum.

 

[olePigeon]

OK, thanks.  6th week of 1987, probably Platinum.  Really wanted it to be beige.

 

[BadGoldEagle]

I think it's gonna be beige.

Just have a look at this listing: https://www.ebay.com/itm/Macintosh-Plus-M0001A-Never-Opened/263276333386?hash=item3d4c7e094a:g:9EQAAOSwFbJZ4~fN

NIB Mac Plus manufactured during the 6th week of 1987. Maybe that's the one you're after? Anyway, this one has the original 1986 box with the beige Plus on the front. Of course they could have used a 'beige' box with a 'platinum' computer...

 

[unity]

I usually just look at the serial, but not the number the color of the label.