Investors rushed to the exits today amid news of a new COVID variant of concern in South Africa, cutting exposure to travel stocks. The gold rally also petered out this week, but battery metal trades and iron ore stocks outperformed. At the close of trade, the ASX 200 shed 1.6% for the week to finish on 7,279.30 points.

Which shares excelled?

Shrugging off some of the regulatory uncertainty surrounding the company, EML Payments (ASX: EML) was one of this week best-performing stocks. The payments firm leapt more than 20% alone on Thursday following news the Central Bank of Ireland will allow the company Irish subsidiary to launch new programs and sign new customers within prescribed growth limits imposed by the bank. 

While the short-term impact of material growth restrictions will still hit the company revenue, EML Payments may be able to have this limit scrapped upon satisfaction of its remediation plan, which management have flagged is due for completion by March next year. 

Elsewhere, a week after it announced the first Nickel Pig Iron production from its Angel Nickel Project is now expected ahead of schedule in the first quarter of 2022, Nickel Mines (ASX: NIC) followed it up with another standout performance. 

If that wasn't enough, Nickel Mines started this week on the right footing with a Memorandum of Understanding (MoU) with Shanghai Decent Investment that will see the pair eye greater collaboration over coming years, including future projects targeting a transition to renewable energy. It will also purchase a 70% stake in a new nickel project, bolstering its production capacity.

Interest continues to flow into battery metals stocks, including lithium producers, with a host of high-flyers showing positive momentum over recent trading sessions. Liontown Resources (ASX: LTR) led the way, however, it was Pilbara Minerals (ASX: PLS), which boosted its finance facility and working capital facility that made headlines. Meanwhile, Novonix (ASX: NVX) and Orocobre (ASX: ORE) all posted solid gains.

After being in the doldrums for months now, iron ore stocks finally made a move higher, although they were caught up in today market-wide sell-off. The commodity, a vital ingredient in steel-making, bounced off an 18-month low amid speculation China steel mills may begin to increase production after delivering larger-than-forecast production cuts. Each of the majors had a bumper week, including Fortescue Metals Group (ASX: FMG), Mineral Resources (ASX: MIN), Rio Tinto (ASX: RIO) and BHP (ASX: BHP).

A licensing agreement was enough to propel Brainchip (ASX: BRN) shares higher, with the stock soaring on Monday, before gains moderated throughout the week. Nonetheless, the AI tech firm has partnered with MegaChips, a multi-billion-dollar global fabless semiconductor company, signing a multi-year licence agreement focusing on the development of its BrainChip Akida IP among external customers' system-on-chip designs.

Which shares dragged on the market?

Shares in Appen (ASX: APX) tanked today after the AI data services firm was hit by a downgrade from Macquarie. The investment bank sees concerns on the horizon for the company, arguing a growing number of companies within the industry are looking to go it alone on the back of privacy and data regulations and leverage their own crowd-sourcing capabilities to undertake data annotation activities. The downgrade hammered APX shares by almost 20%.Bapcor (ASX: BAP) headlined the list of underperformers this week, with the auto parts and accessories retailer coming unstuck by around 15%. The catalyst for the sell-off was news that the company CEO and Managing Director, Darryl Abotomey, plans to exit the business from the end of February next year. After more than 10 years in charge of the company, investors were understandably a little skittish about the surprise development, even though the company reiterated it was on track to meet its FY22 guidance.Having appeared to be on the right track in recent weeks, gold stocks tumbled over recent trading sessions as the precious metal plunged back to earth and hit a three-week low. That meant a number of ASX-listed gold shares struggled, such as Bellevue Gold (ASX: BGL), St Barbara (ASX: SBM), Gold Road Resources (ASX: GOR), Silver Lake Resources (ASX: SLR) and Regis Resources (ASX: RRL).Some of last week struggling names extended their sell-offs, including lithium explorer Sayona Mining (ASX: SYA), wagering technology and data partner Betmakers (ASX: BET), and uranium player Energy Resources of Australia (ASX: ERA). The only one of the trio to release news this week was Betmakers, although its annual general meeting did little to arrest its share price decline, which now stands at more than 25% in the last month.Despite paring some of its losses on Thursday, software firm Technology One (ASX: TNE) had a disappointing week, with shareholders left to rue losses. The company full-year earnings sparked the setback, despite highlighting growth on a number of metrics. Some investment houses attributed the sell-off to the company valuation and the potential for domestic customer growth to moderate from FY24. Tech peers Dubber (ASX: DUB) and Hansen Technology (ASX: HSN) were also left behind this week as the sector dealt with a shift in sentiment, and both company AGMs failed to ignite positive momentum, while travel stocks like Flight Centre (ASX: FLT) and Corporate Travel (ASX: CTD) came under pressure to end the week as concerns mount about a new COVID variant of concern in South Africa.

We'll be back next week with another Weekly ASX Trading Wrap Up - until then, have a great week!