How the JMI indexes are built
The JMI Junior Mining Index measures the Canadian-listed junior mining companies on this platform as a group; the Gold, Silver, Copper and Lithium indexes measure the members whose main commodity is that metal. Every rule below is applied by code, from the platform's own daily closes, and every change to a basket is recorded on the index's page under "Changes".
Who qualifies
The universe is every public, active company on the platform with a primary listing on the TSX, TSX Venture or CSE and a ticker. At each quarterly review a company joins when it passes all of the tests below, measured at the close of the reference date. A company already in the index stays while it meets the looser figure in the third column, so a small move around a threshold does not bounce it in and out.
| Test | To join | To stay | Why |
|---|---|---|---|
| Market value (last close × shares outstanding, C$) | C$5M to C$500M | C$3M to C$625M | C$500M is where "junior" ends on this platform; producers, royalty companies and re-rated developers sit above it. Below C$5M the price feed is unreliable. |
| Share price | at least C$0.05 | at least C$0.03 | TSX Venture ticks in half cents; one tick on a 5-cent stock is a 10% move. |
| Trading history | 60 closes in the feed | same | Three months of closes before a company can be weighted. (In the reconstructed period, when the feed itself was younger than that, 90% of the days the feed had.) |
| Trading continuity | a close on 20 of the last 30 trading days | 10 of 30 | Halted, suspended and cease-traded stocks stop producing closes. This is the observable signal. |
| Liquidity (from the March 2027 review) | median daily value traded over 63 trading days of C$10,000 | C$5,000 | Volume has been recorded since late September 2026; the test switches on once three months exist. |
Which metal a company belongs to
A company's commodity is read from its projects, in this order, stopping at the first rule that answers: an editor's override; the flagship project's commodity; the commodity held by more than half of its projects; on a tie, the tied commodity whose most advanced project is furthest along; otherwise none, and the company sits in the main index only. The assignment is fixed between reviews.
How weights are set
Each member's weight is its market value as a share of the basket's total, with a cap of 10% in the main index and 15% in a metal index. A member over the cap is held at it and the excess goes to the other members in proportion to their market value. Caps are set at each review; between reviews weights move with prices. Free-float adjustment is not applied because the platform holds no float figures. A metal index with fewer than 15 members is equal-weighted and says so on its page; one with fewer than 5 is not calculated.
How the level is calculated
Every index is a divisor index, the arithmetic S&P uses for the S&P/TSX Venture Composite. The level on a day is the capped market value of the basket divided by a divisor:
level = Σ (close × shares outstanding × cap factor) ÷ divisor
The divisor was set so that every index read 1,000.00 at the close of March 2, 2026. It changes only when the basket changes: at a review, when a member is removed, or when a share count is restated after a split or consolidation. At each such change it is rescaled so that the level the instant before equals the level the instant after. A price move never touches the divisor. The indexes are price return in Canadian dollars: no dividends are added back, and every member is quoted in C$.
new divisor = old divisor × (market value of the new basket ÷ market value of the old basket)
When the level is calculated
Every TSX trading day, as soon as the platform's 4:30 PM ET price fetch finishes. Exchange holidays are skipped. A day is published only when: members carrying at least 90% of the weight have a close dated that day; no member moved 50% or more against its previous close without evidence of a split; the index itself moved less than 8%; and the return reconciles to the weighted member returns. A day that fails is marked on the chart as carried or held rather than guessed, and the next day resumes from it.
A member that is halted stays in at its last close. A member whose close is 5× or more the price in use (an unrestated consolidation, or a different instrument under the same symbol) is frozen at the previous price until its history is restated or it leaves at a review; one that moves 50% to 5× without a split on file is held for one day and flows on the next if the second close confirms.
Reviews and changes between them
Baskets are reviewed four times a year. The reference date is the second Friday of March, June, September and December; changes take effect after the close of the third Friday, and the additions, removals and new weights are listed on each index's page. Share counts are taken on the reference date and held until the next review: a financing, warrant exercise or buyback changes a member's weight only at the next review.
| Next reviews | Reference date | Effective after the close of |
|---|---|---|
| Next | 2026-12-11 | 2026-12-18 |
| 2027-03-12 | 2027-03-19 | |
| 2027-06-11 | 2027-06-18 | |
| 2027-09-10 | 2027-09-17 |
Between reviews nothing is added. A member is removed at the close of the day it is taken over, delisted or deactivated, and at a month-end close after ten trading days without a close. A split or consolidation that the platform restates in the price history is mirrored in the share count the same day, so the member's market value and the index level do not move on it.
The reconstructed period
The platform's daily price feed began in February 2026. Levels from March 2, 2026 to the launch date were reconstructed from the stored closes with the same rules, using today's share counts because the platform holds no dated counts from before launch. They are shaded on every chart. Four days in August 2026, when the feed itself was down, are marked carried.
Reading the pages
- Each index page shows the current members by weight, a composition view (weight by metal, by exchange and by size band, with how concentrated the basket is), and every change since the base date.
- On a member's profile, "Against its index" sets the company's price return beside its index over one, three and six months and since the base.
- A member marked "capped" sits at the weight cap; its excess has been spread over the others.
- The metal overlay on the chart is the metal's price rebased to the index's level on the first day shown, so the two can be read on one axis.
Sources and limits
Closes come from the same feed that prices every company page here, quoted from the listing exchange. Share counts come from company filings and websites as recorded on the platform; a count that computes to an implausible market value is held out of the index and reviewed by hand. No dividend, free-float, halt or cease-trade data is held, which is why the rules use closes and market value alone. The indexes are information, not advice, and they are not investable products.