[Och_i30]

The local pot holes (or quarries) have taken their toll on the sidewall of one tyre and so I decided to make it the spare until I get a new tyre fitted.  Interestingly the tread pattern on the spare isn't quite the same as the other four.  They are all Hankook Optimo K415 185/65/R15's.  The car is a Slovakian 2009.5 model and the dealer expected it to be delivered with a space saver or repair kit so the full spare is a bonus.  It's like Hankook changed the pattern around the time the car was built.  Anyone else seen this?

The spare also had 3 orange paper dots stuck on the wheel to mark the position of the balance weight on tyre and rim.  Is this normal?

[Surferdude]

The coloured dots are normally just paint spots on the tyre.

Re the tread variation, it isn't uncommon for a manufacturer to have a few marginally different varieties of a tread pattern. They are normally varied to meet the requirments of different vehicle manufacturers, in accordance with their NVH (Noise, Vibration, Harshness) testing on different suspensions.
In your case I'd say one slipped through the quality control which was meant for some other car manufacturer who also uses them as OE.
They may have been made in different Hankook factories.
Each tyre has a serial number on it which will include a date of manufacture. These 4 numbers are normally at the end of the serial number - such as 2509 which would tell you the tyre was manufactured during the 25th week of 2009.
Before those four digits will be a sequence of letters. Mine say T7DH EK H. Those will tell people at Hankook where the tyre was made and a bit more info besides. If your spare has different letters on it to the four on the road then it will have come from a different factory. If they are the same then it came from the same factory but if that's the case one would assume the date would vary.