Even then the person would only need multiple to compare light & heavy. Would certainly be more difficult since there must be some inconsistency with blister packaging weight itself.
Last week I weighted nine 1st ed Base blister packs. I weighted them multiple times and got the four heaviest one. Opened the blister packs and compared their weight to known light packs I had. Of those blister ones, three had foil cards. It wasn’t easy and i took a big risk. But it was also driving me crazy thinking a fresh Charizard might be in there.
Oh and the difference between a light and heavy pack in ONE gram. Very difficult to figure out when you consider the cardboard blister could have absorbed a bit of moisture or had a nick in it. They all came from the same box.
I would recommend buying blisters over loose in general. But I have some jungle blisters and just weighed them - the heaviest one I opened up and the pack inside was heavy as well. If you have a good number of blisters to compare, I think figuring out which ones are definitely light isn’t too difficult
if you want to open up packs hoping for them to be unweighed, I would contact some bigger names in the hobby or E4 members instead of hoping on ebay
edit: wait that data is definitely messed up because the current PSA pop report includes all 1st editions, including the non-shadowless versions. Also, the last ebay sold listing is incorrect because it was sold by a scammer.
Yeah I remember someone remarking that the best approach for a buyer is to imagine that all loose packs are weighed; but how do you mean contact E4 members?
Some do if they are chasing a pack fresh Holo or just want to know if they should bother opening a vintage pack. Weighing a pack isn’t a bad thing inherently, but selling weighed packs with no disclaimer is bad form.
Any form of weighing eventually hurts most in the hobby.
Seller 1 buys box, weighs, and opens heavies.
Seller 1: Sells light packs as such and doesn’t command a premium for them by being honest.
Buyer 1: Buys light packs at a discount for being weighed.
Buyer 1: Sells loose weighed packs and doesn’t mention what they know to command a higher price.
Buyer 2: Buys weighed pack at normal price thinking Buyer 1 is divulging all info they know about the packs.
Buyer 2: Seller two either weighs or doesn’t weigh and the cycle continues.
This is why a lot of eBay users will pawn off a pack as being "found in a closet/basement"etc because they want you to think they have no idea about the hobby so they’re not weighed. In reality, if their asking price is any ballpark of the going market, they did their research.
I would like to publicly share the following attempt at approximating the weight of a light and heavy base set (first edition or not) blister pack. I know that this is an old thread, but it is well indexed by Google when searching for blister weighing.
TLTR : Blister weighing is not as easy as I thought, read the discussion below.
Note : A light blister has an extremely low chance of containing an holo. A heavy blister has an extremely high chance at containing an holo. In-between is the gray zone where there is a fair chance at opening an holo.
I’m not an expert in pack weighing, I’m not a mathematician and there doesn’t appear to be a consensus. Based on few data points available from public sources, it would appear that the weight range for a pack is around 0.9g and around 1.5g for a blister, meaning that the blister packaging variance is 0.6g. My best effort at computing the average pack weight would be by a weighted average of the (1/3) average heavy and (2/3) average light weights. Here I define “heavy” as having a confirmed holo. I calculate an average of 20.88g. Doing the same with blisters, but with fewer data points and defining “heavy” as 66/100 percentile, I calculate an average of 34.04g. This mean that the blister packaging would add 13.16g +/- 0.3g. This is a very rough calculation, but, interestingly, if I try to compute the same thing using the average of the difference between the heaviest pack and blister and the difference between the lightest pack and blister, I obtain 13.15g. This could be easily confirmed if someone would weigh a bunch of blister packaging after opening them. It appears that the gray zone for a base set pack is between 20.9g and 21.0g, inclusively. Therefor, by my estimations, the gray zone for a blister would be between 33.76g and 34.46g. This is fascinating, because it confirms that weighting blisters is very unreliable and that anything that isn’t in the bottom 1/3 of the weight scale can have an holo. It would define a “heavy” blister as being 34.46g or more. Currently, people appear to anecdotally refer to “heavy” as over 34g or 34.2g. This is because 34.2g would indeed be around the 66/100 percentile, but they fail to account for the increased variance due to packaging.
I mostly used the official spreadsheet for pack weights. For blister weights, the seller of eBay item 333849332436 provided great data (thank you) and I gathered some more from other eBay listings.
I would also like to remind that, although the gray zone is very large, the original owner of a blister box could have weighted each blister and opened them starting with the heaviest and stopped after opening all holos. I do believe that the boxes were limited to 1/3 of holos, that appears to be the consensus. However, since the gray zone is so large, doing so would mean having to open about up to 2/3 of the box. This would be a much more costly endeavor than scanning for bare packs in a booster box. It seems likely that one would stop before opening all holos and, with 24 blisters per box, that may leave a couple behind. It’s also likely and I would say in fact very likely (see the eBayer with 17 of them having a price tag on) that some of the blisters were individually acquired in a big-box store where this cherry picking could prove more difficult.