even though some cheap scales have readability to ~0.002g, it should be assumed that the accuracy for the third decimal point is not very good.
when dealing with potent compounds (i.e. 5-MeO-DMT, etc.) which have doses in the low milligram range (up to 10mg), this is of some concern.
when one has an instrumental limitation such as this, the scientific approach would be creating solutions (dilutions, if necessary):
weigh a mass of 10x a normal dosage, and dissolve with solvent (if the compound is a salt, solvent could be water, ethanol, etc.).
make sure the solute is thoroughly dissolved and in solution before taking an aliquot.

so if a compound is active at 1 or mg, weigh 10g and dissolve in 10ml water, thoroughly mix. now you can take 1mL aliquots. of course, one should be aware of the solubility of the solute in the solvent.

required: mg scale, mL pipette

Nice one benzyme

Thanks

anytime

this is most likely the method by which L is distributed, serial dilutions.
balances which could accurately weigh micrograms would cost in the tens of thousands. $$$$$

Measurement Uncertainty, Significant Digits, etc.

It's fun breathing on milligram scales and watching them change.

True words though benzyme, I'm learning about this in class right now. Boring but actually very important to do accurate research.

Sorry to threadjack, but this question is on-topic.

I have a milligram scale. It comes with 5 and 10g calibration weights.

I tried weighing various dollar bills (some in much worse condition than others because of wear-and-tear) and one 1 dollar bill weighed 1.045 grams. Another weighed 1.000. Another weighed .978 (I tested and retested the weight of the dollar bills, each of them having the same respective weight as the first weigh-in.

I thought it was a problem with my scale so I went to calibration weights. Put the 10g weight on, and it was 10.005
the 5 gram one was 5.000

calibrate before weighing, then repeat weighings.

a good mg scale will have deviation of less than +/- 0.005g, typically around +/- 0.002.

after calibrating an AMW-DIA 10 (american weigh), 100ul of ddH20 was placed on a weighing tray (tared) with an Eppendorf Research 100 micropipette, the mass shown was exactly 0.100g. 96.6uL was then drawn and added to the tared tray, the mass fluctuated between 0.096 and 0.097g.

conc: these scales are reasonably accurate

mmm....I love my microlitre pipettes!

Mind you benzyme, pipettes need calibration too, and you use a balance to do that!

benzyme,

Thanks man! Great post with an elegant, easy to follow, logical procedure.

Peace & Love,
Pandora

yeah, I know
but the Epps are damn accurate in their own rite, little maintenance needed; by far my fav pipette.

L is sold by the tenth g and weighed on analytical balances to the tenth. a g is sold as a ten pack of crystal.After 5g it is sold bulk crystal.
One tenth will make a ten pack of sheets(a book)
1g will make 100sheets(a bible)

Serial dilutions are usually from tenths for vials of liquid.

FWIW
SB

people probably have different methods from maker to maker.
the tenth method probably omits column work, adding to the mass with the extra stereoisomers

IMO, people who make L should at least use a balance that has resolution to 0.0001g.

This is the method for family acid,all family acid. No short cuts are taken on column work with family acid. the tenth method is because very few tenth to 1g customers have microgram balances. Only selling in exact tenths to 5g assures the buyer at least has the means to purchase a good analytical balance if they are buyiing over 5g. and do not need one for lesser quantities as they are precisely wieghed prior to purchase for dilution work.
SB

if that were truly the case, there wouldn't be any amber liquid on the streets.

The amber family acid and the lavender have admittedly degraded in quality but then they never were quality products and have been handled as second rate for decades.Those who produce family silver,fluff and needle point are professional at every point to delivery and the methods have not changed.I cannot speak for "other" vendor /producers as my experience has been with old school acid families and BOEL , the franchise is pulled if "other methods" are used.
SB

it's rather amusing how much ritual and myth surround the L, the most ridiculous being the "week long trip" claim behind thumbprints.

anyway, a semi-micro balance (0.0001g) can be acquired for about $1200. it's a very accurate way of measuring out milligrams
otherwise, a cheap mg scale and a micropipette can do the job very effectively

I 'printed' and you are right the 'trip' really is over after three days. It is the after effects which persist about two weeks.With proper reintegration it is the reason for the print.At least for myself after the 72hr shit yerself in yer piss puddle was over I was gently reschooled on perception and desire as I came out of the mental fugue state.After word I had no more painful emotional baggage over an abusive childhood or personal loss of many friends and family in Viet Nam and soon took up my studies with new vigor and perspective.
High dose DOM lasts longer with much longer mental recuperation time than a solid print but has none of the healing/transformative power of LSD.
Sorry to go off topic, apologies if it was uncool.
WR

nah, that's quite alright
good post.