Gold exchange and scrap gold purchases: recording stock correctly

In a gold shop, stock discrepancies rarely come from sales. They come from two-way transactions: a customer trades an old piece for a new one, sells back scrap gold or brings a ring in to be resized. In a paper ledger these are easily recorded on the money side only, with the goods side missed.

This article describes how each transaction type should affect stock, the shared pricing formula and the stock history details worth keeping for reconciliation.

General rule: every transaction creates a stock history line

Every stock change must come from a specific transaction, never from editing the quantity by hand. Each stock history line records the movement type such as In or Sale, the item, the weight and the person who performed it.

Units must be consistent as well. Money is in VND and weight is in chi, with 1 chi = 3.75 g, rounded to 3 decimal places. When the scale returns grams, the software converts immediately and every related screen shows weight in chi only.

Retail sales and buying gold from customers

A sale reduces the stock of the item sold and creates a stock history line of type Sale. Staff select the customer, scan the item label, and the software calculates labour by jewellery type and issues the invoice.

Buying gold from a customer works the other way: the software creates a new item code and records a stock movement of type In. When creating the purchase, staff choose a product group from the catalogue and enter the product name, so the item is classified correctly and clearly named in the ticket list.

When a customer brings back a piece bought in the shop, scanning its code should show the correct gold type from the original item data, for example 18K or 24K.

Gold exchange: two directions on one ticket

Gold exchange is the easiest transaction to get wrong on paper, because goods come in and go out at the same time. In the software, one exchange ticket does both: it takes the old piece into stock and deducts the new piece from stock.

• Gold in box: item description, weight in chi and unit price for the old piece's gold type
• Gold out box: the new piece, its weight and the unit price for its gold type
• Both boxes take prices from the price list in force when the ticket is created
• The difference to pay is calculated by the system and locked at the payment step

Locking the difference matters. If staff can edit it by hand, the ticket can be right on goods but wrong on money, which opens a gap for fraud.

Scrap gold purchases

Scrap gold is weighed, its purity determined and its value calculated from the applied unit price in VND per chi. Like a purchase, a scrap gold ticket creates a new item code and a stock entry.

The purchase price must deduct loss at the rate the shop actually applies for each gold type and purity. The loss formula should be checked against the shop's own practice before go-live, as this is where purchase prices most often drift from the familiar counter calculation.

Resizing

A resizing ticket does not sell an item but does change its gold weight. The ticket needs the following fields to charge or refund the customer correctly:

1. 1Weight before (chi): weight before the work, entered by hand or read from the scale
2. 2Weight after (chi): weight after the work
3. 3Weight difference (chi) = weight after - weight before, read-only
4. 4Applied unit price (VND/chi): taken from the current selling price for the gold type, not editable
5. 5Gold value difference = weight difference x applied unit price

If the weight after is greater than the weight before, the value difference is what the customer pays. If it is smaller, it is what the shop refunds.

Pricing formula and stock history

Purchases, sales, exchanges, scrap gold and resizing all share one base formula: Amount = Weight (chi) x Unit price (VND/chi), plus or minus surcharges, loss or labour where they apply. The formula should be tested against real transactions before live use.

The stock movement history should open the detail of each line: item, quantity, weight, unit price, supplier, staff member and time. The stock screen needs quantity on hand, and the item detail needs cost price, date received, supplier and the staff member who received it.

At regular intervals, the stock count function is used to count physical stock and reconcile it with the quantity in the system.

Frequently asked questions

Does gold bought from a customer go into an existing item code?

No. Every purchase creates a new item code and a stock history line of type In.

Should a gold exchange be split into a purchase and a sale?

No. One exchange ticket takes in the old piece, deducts the new piece and calculates the difference to pay.

Why can staff not edit the exchange difference?

The amount is calculated from the weights and unit prices in the two boxes. Manual edits easily cause wrong figures and create a gap for fraud.

Do we need to show weight in grams?

No. The scale returns grams, but the software converts to chi on weighing and screens show chi only to avoid unit mix-ups.