How this site’s figures are produced

The price on this site is the Central Bank of Sri Lanka’s daily gold price in rupees per troy ounce, divided out into the units and karats Sri Lankans use. This page describes where that figure comes from, how it is checked, and what this site refuses to print.

One published figure, divided out

The Central Bank of Sri Lanka publishes a single gold price each business day: rupees per troy ounce. That ounce figure is the only number the bank issues, and it is the root of every cell on this site. A troy ounce is a fixed weight, so the price of one gram is the ounce price divided by that weight. The pawn of eight grams and the ten-gram bar are then simple multiples of the gram. There is no independent pawn price from the bank; the pawn is a local unit that this site derives from the ounce.

The karat rows are also derived. The bank’s ounce price is for fine gold, that is, twenty-four karat. A twenty-two karat row is the twenty-four karat figure multiplied by twenty-two over twenty-four; a twenty-one karat row is multiplied by twenty-one over twenty-four, and an eighteen karat row by eighteen over twenty-four. Because every row comes from the same ounce price, the ladder can never disagree with itself. If the ounce moves, every row moves in proportion.

Where the reference is read and checked

The Central Bank’s gold price is read from its exchange-rates page once each business day. The bank does not publish on weekends or public holidays, so those days are absent from the day-by-day page. The price is struck at the start of the business day, using the world gold price in US dollars and the bank’s own indicative dollar to rupee rate. It is a reference, not a market that trades all day; the Sea Street dealers’ price can move later and is set by the All Island Jewellery and Pawnbrokers Association. That association does not publish a daily table, and this site does not print its rate.

A reading is refused if it fails any of several checks. If the ounce price falls outside a plausible band, if it moves more than eight per cent between two business days, if it sits more than five per cent from the independently computed world price, or if the latest price is more than four days old, the new figure is not shown and the previous one remains on the page. This prevents a single bad number from misleading a reader.

The world metal and the rupee

The world price of gold is read in US dollars per troy ounce from one source, and the dollar to rupee rate is read from another. The two are multiplied to produce an independent world price in rupees. Neither figure is taken from the Central Bank’s page, because using the bank’s own inputs would make the check circular. The independent world price is then compared with the bank’s reference. The two should sit within a point or two of each other because they measure the same metal at nearly the same moment, but they can differ because the reference is struck at the start of the business day and the world figure is read later.

A gap between either of them and a shop quote is not a mistake in the reference. A shop quote includes a making charge for the jewellery and a margin for the seller, and a pawnbroker’s slip includes a valuation for a loan. Those costs are real and local; they sit on top of the metal price. This site cannot measure them, so it does not print a shop price.

What this site refuses to print

This site does not print invented shop prices. It cannot observe the making charge that a particular jeweller adds, nor the margin a pawnbroker takes, so it does not guess. It also does not print forecasts. The gold price can move on news, on the dollar, or on the rupee, and no one can promise a direction. Past prices are shown as the bank published them, with no comment on what they imply for tomorrow.

It also does not print a 'live' figure that is only a markup. Some sites take the bank’s reference and add a percentage, then label the result a live price. That figure is not live; it is the reference plus a fee, and the fee is not disclosed. This site shows the reference itself, with the date it belongs to, and leaves the markup to the shop that will charge it.