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1 ml of concentrate =/= (does not equal) 1 gram

Discussion in 'Concentrates' started by herbivore21, Oct 13, 2015.

  1. herbivore21

    herbivore21 Well-Known Member

    Messages:
    4,278
    So this is something that has bothered me for a while. Most retailers of concentrates seem to decide arbitrarily that 1ml as measured in a syringe that the concentrate is sold in is equal to 1 gram of the same.

    Now this idea is based on the fact that 1ml of pure water at the right temp/barometry will weigh 1g.

    However, being that grams are a measure of mass, whereas mls are a measure of volume, the relationship between the two is not constant for all substances, only water, and only in the right conditions.

    I'd really love to get some volunteers that live in places where they can go to a dispensary to buy a 1ml or .5ml syringe (whatever volume really), take note of the volume and squeeze the entire contents onto a scale. Let's get an idea of what amounts are being passed off as grams because of this oversight on the part of most of the industry ;)

    Please do join in and post below if you would like to take part.

    I think we should keep these reports consistent, so please identify the nominal mass and volume (how many grams advertised on the label, how many mls in the syringe) and the actual mass (weight in grams/mg) and the state where you bought it. If you like, you can identify the product/dispensary/extract artist, but if you prefer not to disclose this, I understand!

    Looking forward to seeing what we learn here! :D Thanks in advance for all volunteers :D
     
  2. Monsoon

    Monsoon Well-Known Member

    Messages:
    1,513
    Location:
    Canada
    Can't help but another way would be to make note of the weight at the start and then weigh it again when it's empty if people don't want to empty the contents out all at once.
     
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  3. herbivore21

    herbivore21 Well-Known Member

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    4,278
    Could do this as well :)
     
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  4. tepictoton

    tepictoton Well-Known Member

    Messages:
    1,413
    Location:
    a funny place called earth
    Other way around would be to gently heat concentrate till liquid, then see how much of one gram you can get into a 1ml syringe.

    Another really quick way would be to drop some oil in water and see if it floats it sinks... That way you at least know if 1 ml will be more or less in weight then water.
     
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  5. GuyLeDuche

    GuyLeDuche ^ "Eat a bag of Dick's!"

    Messages:
    291
    Location:
    WA State
    Well I think results may vary depending on what is added to the oil in pre-fills, but I weighed up a little I had around. I don't have any oil I want to melt atm, but I have exactly .5mil in a syringe of co2 mixed with EJMix at "1:2" ratio. Of course I used the old and obviously inaccurate method in the OP of 1 gram to 2 mils, but for me it's accurate because that is the mix that people like lol. On to the point, .5mils at this mix weighed .29g. I'm not sure this is helpful, as I think the question was about the oil itself, but at least a baseline...
     
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  6. EpicNameGuy

    EpicNameGuy Well-Known Member

    Messages:
    108
    Not to muddy the waters here but a couple worthwhile notes:

    1) Concentrate batch-to-batch is likely to have variation in the weight of 1ml due to a couple of things, one of which is the fact that concentrate is not a single compound, like water. If your concentrate is 60% THC, for sake of conversation, you have to ask what is the other 40%? Wax, terps, solvent, water, crazy moon material? It definitely contributes to the weight and would potentially affect your result sample-to-sample.. can't speak to how much of an affect it would have, but some I would assume. Which brings me to...

    2) Similar comparisons have been brought up in the past IIRC, and the consensus was 1ml concentrate was extremely close to a gram. I could be wrong here, but that's what I recall at least.

    Also, I am in a state that has a medical framework but is still rolling it out. However, I do work at a testing and extraction lab. Any carts or syringes that we are producing are generally not straight concentrate. There's usually a medium added to facilitate flow. So in that case, that makes the comparison harder unless you have a syringe of un-cut, for lack of a better term...

    Lastly, if you really want to get to the bottom of the quality level of your concentrate, I think the most direct way would be to submit a sample somewhere and have it tested. A cannabinoid test for a liquid (if it's in a syringe, we deal with it as such) at the lab I work for would require .5ml to test, for example.

    Just some initial thoughts to consider.
     
    Last edited: Oct 13, 2015
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  7. herbivore21

    herbivore21 Well-Known Member

    Messages:
    4,278
    This is great feedback, and illustrates my point. The usual thing I see is what is advertised as a 'gram', sold in a syringe filled up to 1ml (which is purported to be equal to a gram, which is because 1ml of pure water in the right conditions weighs 1g). However, what you are expressing here illustrates my point. Given the 1ml to 1g assumption almost across the board that I have seen for syringe concentrates, you should have had .5g of weight in .5ml

    In fact, you had almost half that amount. You are spot on to observe that different mixtures of different substances (ie: pure decarbed oil vs mixed with solvents like VG/PG/PEG/ethanol) will end up with a different mass to volume ratio. Different consistencies of extract from the same material will even vary on this.

    Thanks for your feedback brother. Nice to hear from someone in the industry!

    As we've seen above, 1ml would be more like .58g for that particular ejmix/oil solution, for other various kinds of concentrate this will vary as I'm sure you'd agree for the gross volume of a given substance to gross weight of the same. For example: concentrates that have been decarbed and terps added (xtractology specifically have some products like this in Cali that I have heard good things about) will likely vary on this ratio from the above ejmix/oil solution and from fully decarbed oil with nothing mixed in sucked up into the syringe hot off the dish. I expect to see variation across samples here according to many factors that effect the composition of the oil/solution.

    My take home message and why I've raised this topic is this though:

    In my view, if you sell oil and you sell it in syringes, it is not accurate or honest to call 1ml of oil 1g or assert this relationship.

    I am talking here about retailers, I have heard of many cases where a retailer directly asserts that the 1ml of whatever mixture/extract/solution in the syringe they are selling weighs 1g gross of the product in question.

    I do appreciate as you say that in some cases, where the 1g reference is to net actives rather than gross mixture (such as solvents/carriers to liquify and make the whole syringe part of the equation practical), there will be variation and that this can still be a version of 1ml = 1g that we can consider accurate. This is not the kind of claim being taking to task in this thread ;)

    There's nothing wrong with selling 1ml of any given mixture and labeling it 1ml or labelling the weight of actives in the product (when mixed), the problem comes in when you imply or assert that that 1ml of any gross volume of substance represents 1g of gross weight of the same - because this is simply not likely to be true in most cases. Of course, this is not directed at you personally man (you are not a retailer from the sound of it lol), this is a general observation :)

    Thanks for your input though and glad to make your acquaintance as well my friend. You will surely have a wealth of information that we can call upon in future :D

    I actually am going to take part in this experiment myself when I get time, I'll perform a full decarb on some old material and suck it up warm into a german boro lab syringe that I have to see what results I get on this kind of material. I'd still love to see as many reports as possible, thankyou so much to @GuyLeDuche for contributing so far :D

    I look forward to seeing the results we get!

    Again, I believe this to be a industry wide practice so I don't think anyone should be singling out vendors and giving them flak. I believe this is something that those in relevant jurisdictions should investigate and then can use as a basis to suggest change to the industry :)
     
    Last edited: Oct 13, 2015
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  8. EpicNameGuy

    EpicNameGuy Well-Known Member

    Messages:
    108
    Thanks for the kind words. Likewise friend! I'm certainly no big shot in the industry by any means. But it's definitely very cool being a part of it, especially from a lab perspective. I may not be able to answer much but always willing to field questions.

    Sounds like I was misunderstood, and your issue is with unadulterated oil being sold as 1ml that they claim weighs 1 gram.

    I feel as though I read somewhere on this website (perhaps in the canna-cig-juice related threads) that someone confirmed it was close enough for the sake of conversation when they were discussing their PEG / EJMix ratios. If that's true, yeah I'm sure it is less. It would be interesting to see the results here to determine by how much though.

    If I happen to come across any decarbed oil in my stash I'll see if I can contribute.
     
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  9. GuyLeDuche

    GuyLeDuche ^ "Eat a bag of Dick's!"

    Messages:
    291
    Location:
    WA State
    Jus wanted to throw this out there... I was mixing up a tank and put .5g (co2) in the dish then pulled 1ml Ejmix and after adding it I was at 1.58g. So EJ at least is close enough to 1ml=1g for my purposes at least, for all I know I over-pulled with the syringe lol...Not a scientist...
     
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  10. geofreller

    geofreller Member

    Messages:
    5
    Yeah it's not 100% exactly the same, but but so close that for all intents and purposes 1g. Concentrate = 1mL = 100 units (some syringes are marked in units).
     
  11. herbivore21

    herbivore21 Well-Known Member

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    4,278
    How can it be 'so close' across the board though? Different extracts have radically different compositions. The density of these constituent chemicals determines the discrepancy between the volume and mass of the product. This means that this should vary as much as the content of extracts can vary.
     
  12. geofreller

    geofreller Member

    Messages:
    5
    You're right they do vary by a few percent in mass/volume. But a few percent of 1g. is such a small mass that the wind turbulence from your breathing a few feet away can be more forceful. If you are talking lb's or kg's then that small percent difference should be considered. Bottom line: Equal volumes of cocentrate and water do not have an equal mass. This wil result in +/- 1 dab per mL. It is a dumb (but valid) way to label, because the standard is in grams, but the discrepancy is very trivial at these amounts.
     
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  13. Jman5280

    Jman5280 Well-Known Member

    Messages:
    590
    The cartridge I bought didn't specify weight, at least I don't think so.

    The cartridge reads: .6ml (when I hold it upside down).

    The label says: 750mg with 500mg of total cannabinoids
    *(which I'm confused what this even means. Why does it say 750mg and 500mg? What is the other 250mg? This oil is supposed to be cut with nothing).

    I'm so confused. What do I actually have lol?

    Why are the numbers on the carts upside down?
     
  14. stinkytofus

    stinkytofus Well-Known Member

    Messages:
    398
    I had .65 oil added 10 drops should be 1.15gram/ml

    I barely filled a 0.5 ml cart

    Wth? Isnt it suppose to be double ?
     
  15. herbivore21

    herbivore21 Well-Known Member

    Messages:
    4,278
    No cannabis resin is totally made up of cannabinoids. I am very thankful for this, as cannabinoids are very boring without terps.

    Holy shit! So is that .65g of oil you had and you added 10 drops of terps? If you added terps, that solvent action of the terps could easily make the same weight of oil occupy a smaller volume - concentrates that have less overall terps can be much more voluminous than the less viscous oil that you get when you mix terps and those terps dissolve the oil down.
     
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  16. stinkytofus

    stinkytofus Well-Known Member

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    398
    I put ej mix not terps
     
  17. herbivore21

    herbivore21 Well-Known Member

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    oh I see, regardless, the same principle applies, solvent (ejmix) dissolves and hence should be expected to reduce volume of what was already there.

    Remember, volume is a measure of how much 3d space a given substance occupies. This is different from the weight of the item and you can add to the weight of a substance in a way that reduces the volume, depending on the properties of the substances present.
     
    Last edited: Jul 24, 2017
  18. OldNewbie

    OldNewbie Well-Known Member

    Messages:
    717
    In a thread that is trying to explain that while a ml of pure water at standard temperature and pressure is a gram does not mean a ml of some other substance at room temperature and the pressure where one is at is also a gram, it might be best to write precisely. Is "mass" a measure of "weight"?

    For our usual purposes, sure. In this thread?
     
  19. herbivore21

    herbivore21 Well-Known Member

    Messages:
    4,278
    Strictly speaking, from a physics perspective (and I am no physicist), mass is not exactly the same as weight. However, for our purposes here I was using the term mass in the lay, everyday usage of mass which is synonymous with weight. My explanation was that the weight and volume are not the same thing and you can add weight, but reduce volume in some cases depending on the properties of the substance. It might mean that the comment that mass is a measure of weight is not very insightful as a stand alone sentence, but the language that I used still serves to illustrate that the weight/mass (both measured in g/kg) of the substance can be different to the volume. That was the intended message.

    If you'd like to provide a full write-up on the scientific distinction between mass and weight, please do assist my friend :peace:

    For what it's worth, the OP is edited now to remove the term mass altogether.
     
  20. stinkytofus

    stinkytofus Well-Known Member

    Messages:
    398
    So in another words the ejmix is like water, the cannabis oil is like sugar, once u throw it in it will make it heavier but will not increase volume by much
     
  21. herbivore21

    herbivore21 Well-Known Member

    Messages:
    4,278
    Well actually, have you seen a large mass of honeycomb wax? It has obviously got empty volume there, as in the honeycomb holes in the wax mass are empty pockets with air.

    Pour a small amount of hot iso (heating the solvent increases the solubility with the corresponding solute; in this case, the cannabis resin, cold iso would require a large quantity of iso to be used which would increase the volume occupied by the solution) onto the honeycomb wax, and the honeycomb dissolves.

    You now have a gooey liquid which is obviously going to be heavier than the resin was alone before the solvent was added, but due to those empty pockets of space in the honeycomb wax having been eliminated (as it has been dissolved now), may occupy less volume than it did previously.
     
    Last edited: Jul 24, 2017
  22. OldNewbie

    OldNewbie Well-Known Member

    Messages:
    717
    I understand why the error was made and assumed it is because the difference in gravity between a lab at sea level or a lab high in the Rockies is so slight so as to be little more than a rounding error. I guess it just depends on how precise our question is.

    I remember, as a lad, working in inventory at a place that sold precious metals (gold, platinum, palladium, silver) in near-raw form. (Wire, bar, shot etc.) Historically, the law recognized it was both important and difficult to know the amount of gold in a sample so came up with the carat/karat markings. (24kt = "pure" gold, 12kt = 1/2 gold + 1/2 alloy) A popular mix was/is 14kt gold.

    The theory of the mix and the reality of smelting it were at odds and the law in the U.S. also allowed for a 1/2 karat error to reflect that reality. While the law was changed in 1983, smelting techniques had gotten better before then and most of the wire we sold was 13.5 karat...precisely. This was sold to the jeweler who saved 1/2 karat gold cost of the material while still being able to legally sell it at the popular 14kt purity.

    Interesting historical factoid other than the issue being discussed in this thread. I agree with you there needs to be some recognition of the difference between the theory and the reality of what is being sold. Until there is some standardization in the industry, the connection between the two has been demonstrated by you to be tenuous at best. The difficult part is standardization tends to come from regulation and there cannot be nationwide regulation unless and until the federal government reschedules cannabis.

    Until then, with the many things that can affect the amount of "stuff" it appears we are buying, without testing we have to rely on the manufacturer to let us know how it came up with the numbers on the side of the package.
     
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  23. Gn0sis

    Gn0sis Well-Known Member

    Messages:
    150
    On packaging of these KingPens, it says "half gram"

    Empty King Pen cartridge:

    [​IMG]


    Full King Pen cartridge:

    [​IMG]


    oil is nice and thick. tastes like the strains. pretty satisfied with these :)
     
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  24. herbivore21

    herbivore21 Well-Known Member

    Messages:
    4,278
    Very interesting comparison there man! Thanks for sharing!

    The actual difference between mass and weight on earth can be little more than academic as you allude, but the difference can have real implications in some contexts as you also said above. It is amazing how regulatory standards can allow vendors to get away with misleading packaging and claims isn't it man?

    I am glad to see our friend @Gn0sis share that some pens are being sold with an advertised weight of errl vs volume measures as many do. At least some people are being ethical here! I obviously produce all of the meds that I consume, but if for some reason my health deteriorated and I couldn't, I could tell you guys one thing - I would never buy a cannabis extract that was measured in volume and not weight.

    I've had concentrates that are denser than most anything I've ever seen before, and then concentrates that were the opposite - airy and voluminous - as well! I've been in situations where I've had equivalent weighted pieces of hash and the one that is pressed with some heat occupies half the volume of the one that was not pressed and had no heat applied! Volume is simply not a very helpful measure of how many doses of medicine one is looking at. :2c:
     
  25. DieHard

    DieHard Vertical transportation specialist.

    Messages:
    3,144
    Location:
    Limbo
    I get syringes of distillate that are made by Xtractology and I have noticed that they are consistently filled to 4.5 ml. However, I also have a syringe of Raw distillate (much older batch) from the same manufacturer and it is filled to 5.0 ml. I think they are now filled with a robotic machine (they posted a pic of one on IG) by weight.
     

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