Apple saw 50 billion US dollars (£32 billion) wiped off its value today despite another bumper profits announcement.
The technology giant was given the thumbs down by Wall Street as its latest update failed to provide much detail on the performance of its new smartwatch and gave a cautious outlook for the current quarter.
In London, the Apple slump - which also fed into other stocks in the sector - was among a cocktail of factors that saw the FTSE 100 Index slide by more than 100 points during the session.
Blue-chip shares were also dragged down by falls in metal prices and oil, as well as minutes from the Bank of England's latest interest rate meeting suggesting that a number of officials are moving closer to voting for a hike.
Technology firm ARM Holdings was the biggest faller on the FTSE 100, despite reporting a 22% rise in quarterly revenues. Its chip designs help to power Apple products.
Apple's shares were down by nearly 7% after markets opened in New York today, equivalent to a 50 billion US dollar hit. They had fallen even lower during after-hours trading last night.
The company announced profits of 10.7 billion US dollars (£6.8 billion) and revenue of 49.6 billion US dollars (£31.8 billion) - led by record third quarter sales of both the iPhone and its Mac computer lines.
However, no specific numbers were given for the sale of the Apple Watch, which launched in April, with the firm referring to it only as a "successful launch".
The Apple Watch appeared in the Other Products category in the results, a category that grew by 952 million US dollars (£609 million) on the last quarter, lower than the 1.8 billion US dollar (£1.2 billion) watch sales that analysts were expecting.
However, Apple said that revenues from the watch had been well over 952 million US dollars and that their growth had been offset by declines from iPods and accessories, which are within the same segment.
Meanwhile, the company's central expectation of 50 billion US dollars (£32 billion) in revenue for the quarter ending in September was a little below the average number that had been pencilled in by analysts.
In total, the California-based firm sold more than 47 million iPhones between April and the end of June, as well as 10 million iPads - a further drop in sales for the tablet, which has been in steady decline.
Richard Hunter, head of equities at Hargreaves Lansdown stockbrokers, said: "This is yet another set of eye-watering numbers from a company which continues to lead the world in its space.
"Set against the weight of expectation, however, and with a relatively undemanding outlook for the final quarter, the shares fell prey to a wave of selling.
"Apple remains a technology juggernaut despite the disappointing reaction to the numbers, although even this needs to be taken in context with a share price that had risen 38% over the last year."
Elsewhere in the sector, rival Microsoft reported a 2.1 billion US dollar (£1.3 billion) quarterly loss, the biggest in its history as it was dragged into the red by its 7.6 billion US dollar (£4.8 billion) purchase of Nokia.