Two sizes, one gold bar: how far the prices drift
The Korea Exchange gold market lists two sizes of the same metal — a 1kg bar and a 100g mini bar, both 99.99% fine, both settled on the same venue. They do not close at the same price per gram. Across the 66 sessions we hold, the mini bar closedmore expensive on 42 days and cheaper on 24.
What "premium" means here
One number, computed the same way every session: the 100g close divided by the 1kg close, minus one. A positive figure means the smaller bar was dearer that day. Both series come from the same daily commodity files we collect, matched by trading date —66 files read, 66 days with both sizes present,0 days we could not pair.
The widest sessions
Ranked by the size of the gap, not by date. Negative means the 100g bar closed cheaper.
| Session | 1kg close | 100g close | Gap | 1kg volume | 100g volume |
|---|---|---|---|---|---|
| 2026-09-09 | KRW 191,000 | KRW 193,000 | 1.047% | 212,682 | 13,283 |
| 2026-09-03 | KRW 194,190 | KRW 195,900 | 0.881% | 238,883 | 5,119 |
| 2026-09-07 | KRW 190,630 | KRW 191,850 | 0.640% | 229,422 | 8,109 |
| 2026-09-11 | KRW 189,160 | KRW 190,340 | 0.624% | 279,355 | 9,140 |
| 2026-09-02 | KRW 190,810 | KRW 191,880 | 0.561% | 251,698 | 15,432 |
| 2026-09-21 | KRW 193,370 | KRW 194,300 | 0.481% | 150,072 | 6,219 |
| 2026-08-28 | KRW 203,010 | KRW 203,950 | 0.463% | 166,473 | 5,315 |
| 2026-09-29 | KRW 181,460 | KRW 182,250 | 0.435% | 220,161 | 15,165 |
| 2026-08-27 | KRW 205,650 | KRW 206,480 | 0.404% | 295,356 | 9,900 |
| 2026-08-26 | KRW 207,500 | KRW 208,300 | 0.386% | 322,057 | 13,087 |
Do the two sizes move together?
On 59 sessions both sizes closed in the same direction; on 6 they split — one up, the other down, same metal, same day. On 1 we could not tell, because one side had no change field we could read. We record that rather than counting it as agreement.
The volume gap is the larger number
The median 1kg session turns over 210,736 against 9,787 for the 100g bar. The two sizes are not the same market in any practical sense, and the thinner one is where the wider closes sit.We are not saying thin trading causes the gap — we have not tested that, and this page does not claim it.
What this page does not tell you
- Why the gap moves. Dealer spreads, retail demand for small denominations, settlement handling — all plausible, none measured here. We counted the gap.
- Whether either size is mispriced. A persistent difference between two contracts is a fact about the order book, not a verdict on value.
- What you should buy. Nothing on this page is advice. It is a distribution, not a recommendation — and a distribution is not a statement about you.
- History beyond this window. 66 sessions, 2026-07-01 to 2026-10-07. We hold what we have collected. A longer series is a possible follow-up, not a claim we can make today.
Source: the daily Korean commodity closing files we collect, filtered to the KRX gold market's two 99.99% contracts. Every figure on this page is computed at build time fromgold-bar-premium.json; none is transcribed by hand. Days where only one size was present are reported as unpaired rather than filled in.