The FTSE 100 briefly rose above 6,400, got a nosebleed and slipped back below that level again, though it remained in positive territory.
The top-share index was up 18 points at 6,372 at 12.35pm, largely on the back of mining stocks.
As usual, however, the eyebrow catching movements were to be found at the more bijou end of the market, even though the FTSE Aim 100 was more or less unchanged at 3,461 and the FTSE Aim All-Share was just 1.4 points firmer at 735.
Gaming and tech holding group Webis Holdings PLC (LON:WEB) was a favourite with the punters, more than doubling in price to 158p after its main US subsidiary, WatchandWager.com, extended its contract with the French Pari Mutuel Urbain (PMU) to provide customers access to direct betting into French horse racing pools.
Investors also tucked in to Harvest Minerals Limited (LON:HMI), which rose by more than a third to 5.5p after the potash producer's first quarter activities report.
The company had submitted samples from the initial air core drill programme to the laboratory for analysis and expects to be able to announce the results early next month.
Stock market star 88 Energy ltd (LON:88E), up more than 400% this year, was at it again, advancing 17% to 2.28p as it confirmed 200,000 new shares had been issued as a result of share options being exercised.
It was a case, as Del Trotter might say, of lovely Jubilee, as Jubilee Platinum PLC (LON:JLP) motored almost 9% higher to 3.08p as the company reported increased processing capability at the Dilokong chrome mine to 75k tonnes per month (tpm) from 25k tpm.
Kolar Gold Limited (LON:KGLD) was down almost 13% after a seemingly innocuous announcement about appointing Smaller Company Capital Limited as its joint broker, alongside N+1 Singer. Wise heads know that such appointments often – though not always – come just before a big share issue.
Also on the slide was Serica Energy PLC (LON:SQZ), despite reporting its first annual profit since 2009.
The company's shares fell 7% to 10.35p as it said it was on the look-out for acquisitions.
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Top riser in London was gaming and tech holding group Webis Holdings PLC (LON:WEB) after its main US subsidiary WatchandWager.com extended its contract with the French Pari Mutuel Urbain (PMU) to provide customers access to direct betting into French horse racing pools.
Shares galloped up almost 59% to stand at 1.15p a pop. The FTSE AIM100 index was up 0.22% to 3,468.
FTSE AIM All share was also ahead at 735.440 - up 0.26% while big cap miners were bolstering bigger cousin FTSE100, which stood 0.77% or 48 ahead at 6,402 at the time of writing.
Silver giant Fresnillo (LON:FRES) was top of the tree, up 4.64% to 1,058p. Commodity stocks were up this morning as crude prices firmed, helped by news of a strike by oil workers in Kuwait.
It comes after yesterday's monstering of oil shares in the wake of the deadlock at the oil producers' meeting in Doha.
BP (LON:BP.) shares added 1.64% to 361.6p, while Shell (LON:RDSB) added 0.39% to 1,812p.
Closely followed under the cosh Gulf Keystone Petroleum (LON:GKP) bounced back a bit after a torrid time, adding 21.28% to stand at 5.70p each. Last week shares fell 45%. The only news out was a regulatory statement revealing 2015 accounts had been sent to shareholders.
Metminco (LON:MNC) shares added 1% to 0.202p as it told investors it expects to complete the acquisition of the Seafield SAS, owner of the Quinchia gold portfolio in Colombia, by the end of May.
Three engineering firms have been short-listed to complete the feasibility study started in 2013 by Seafield for the development of the Miraflores mine.
Silence Therapeutics PLC (LON:SLN, OTCMKTS:SLNCF) added over 5% to 132.9p as its chairman and chief executive bought shares in the company.
Ali Mortazavi purchased 160,000 shares at a price of 125p per share, taking his holding up to 1.94mln shares, equivalent to 2.78% of the issued share capital of Silence.
On the flip side, Shanta Gold (LON:SHG) dipped over 4% to 8.24p as it restated its production guidance for the year as it updated on its performance in the first quarter.
The company, which owns the New Luika mine in south-west Tanzania, produced 24,341 ounces of the yellow metal in three months ended March, compared with just 29,000 ounces in Q4.
It sold 21,486 ounces at an average price US$1,132 an ounce, which was just US$51 below the spot price.