Deposit chits are issued by Frontierswoman's League Trading Houses to indicate the amount and quality of materials someone deposited at one of these trading houses.
They can be used to later withdraw the same amount and grade of stored material at any of the League's trading houses.
Deposit chits are useful primarily for trade. In Sector LK96-51 where transmissions to and from the Central Bank are carried by Norvelios cruisers on their months-long cycles credits are only an option for the patient, and if you don't regularly deal with Norvelios then N-Scrip won't do you much good. So, for many League members chits are the de facto currency: backed by the goods on deposit at a Trading House.
These chits appear as coins; being small, flat, and usually made of metal. Each chit is engraved with the information needed to identify the stored material it represents:
Substance (ex. copper, quartz, neon)
Amount (ex. 13 kg, 1.47 Mg, 863 g)
Grade: this is a number from 1 (most pure, highest quality) to 5 (least pure, lowest quality) assigned by the trading house assayers with tests appropriate to the material in question
Storage Cost Markings (where applicable; includes date storage began and storage cost rate)
It's common for the chit to be made out of the same material as what has been deposited, if it's of a suitable substance. It's often a piece of the deposit itself.
Deposit: A percentage of the material deposited will be taken as a fee for the deposit and the issuing of the chit.
This same fee applies for adding more material to an existing chit.
Smaller Denominations: The Trading House will also issue several chits of smaller denominations covering a single deposit for a smaller additional fee. You can also split chits for the same fee. This is useful if you plan to trade the chits to someone else.
Examples
You owe Maddis Geuyong 50kg of tungsten after he spotted you for some new mining bits. Lucky for you that your last mining session produced 78kg of tungsten. You can deposit your spoils at a Trading House, putting 50kg on one chit and the remaining 28kg (minus fees) onto another.
You just hit a huge payday running phosphorous to a farming collective on Qing Parkash. They paid you in a chit for 100kg of uranium, but you aren't planning to make any purchases that big in the near future. So, you split it up at a Trade House into more manageable 10kg and 1kg denominations.
Withdrawal (Same Substance): No fee for withdrawal. This includes updating the remaining amount of the deposit on the chit, or voiding the chit if no material is left in the account after the withdrawal.
Withdrawal (Different Substance): You can withdraw a different substance at the current exchange rate between the two substances set by the Trading House. No fee for withdrawal. This includes updating the remaining amount of the deposit on the chit, or voiding the chit if no material is left in the account after the withdrawal.
Storage Costs: You can use a chit to pay for storage at a Trading House. When used in this way information about the storage is added to the chit: the start date and the rate. This allows anyone looking at the chit to calculate its current value. More information on this topic can be found in the article League Storage Tokens.
Members of the League do have the option of linking any deposits to their Frontierswoman's League account. This is more secure as only they will be able to access those items backed up by biometric data.