CZECH REPUBLIC - "one-off" vinyl pressings
this items have been made by the gz vinyl pressing plant in the czech republic. the matrixes have the same aspect and pattern available also on the nevermind czech 12" and on other records confirmed as being made by this plant.
one or two copies only have surfaced for each item, and it's not clearly defined what they are. if they were fake pressings, made for profit, there would have been several copies around, as they are usually pressed in runs of at least 500.
they may be one-off items sent to clients who requested samples of the plant's production (at least the nevermind 7"), 'test' pressings for (official or unofficial) releases that were later cancelled, some employee playing with the machines, or something else.
a mail with some questions has been sent to the pressing plant, but they haven't replied...

media 7" picture disc
code -
matrix machine printed side a MZO 0154/A side b & JH 0037/A
pictures white vinyl: side a, side b. translucent pink/purple vinyl: side a
notes the record doesn't play nirvana music. it's claimed to be a visual test pressing for an australian double 7" picture disc release, later canceled. there were no pressing plant in australia who made picture disc (the australian oh, the guilt 7" picture disc was made in the usa), so it's possible that the label requested a sample from the czech plant.
other than the matrixes, these pictures also confirm that it was pressed by gz vinyl:
12" side a and b, 7" side a detail
the picture used is exactly the same as on the 12" picture disc, cut to fit the 7" format.
on side a of the 7" there's even a cross marking the position of the spindle hole on the 12".
two colours of vinyl have been used (visible from the record rim): white and translucent pink/purple.

from joris baas, previous owner: It was sold to me by an Australian, more than 10 yrs ago (before 1996) who told me he got it from Geffen Australia. The fact that there was no Nirvana music on there he explained as saying it was a visual test pressing (marketing department?) so they had the picture disc run with a pressing of some 7".
from paul roberts, owner: I contacted the record store where I bought it and the owner can't recall the disc itself, but he did buy in a number of items from the Czech distributor. I’d say he got it with a bunch of stuff because I bought the Nevermind 7”, Green Nevermind 12” and the Platinum (PLATIN) Nevermind CD all at the same time.
from vaughan bowden, owner: Side a has 2 tracks on it sung in English and plays at 33.
Side b has 1 track on it sung in some Eastern European (?) language and plays at 45.

some more info on this pr3 page

thanks to joris baas, a.sohier, gianluigi valerio, paul roberts, vaughan bowden
and andi frick, owner of 'sheep records'

media 12"
code -
matrix MZM 6187/A no matrix on side b
pictures front sleeve
notes white label, plain die cut sleeve with a title sticker. claimed to be a japanese release
related items: hormoaning official and unofficial releases

the go team - scratch it out / bikini twilight
media 12"
code KTGT016
matrix side a MZM 6185/A no matrix on side b
pictures sleeve detail
notes one sided, white label, plain die cut sleeve with a title sticker
related items: scratch it out / bikini twilight us 7"
thanks to chris spicer