LONDON -- The FTSE 100 (INDEX: ^FTSE) has struggled over the past quarter, with its ups and downs in response to ongoing world and eurozone crises leaving it with an overall fall of 170 points, to around 5,600 at the end of June.

But the index is just the average of all of the shares it contains, and just as there have been some that have performed outstandingly well, plenty have slumped badly. Here are three...

Falling miners
Falling commodity prices have made this a very tough quarter for metal and mineral producers, and all the big FTSE miners are down. But one that has suffered more than most is Lonmin (LSE: LMI.L), whose price has fallen by 244 pence to 778 pence, for a 24% drop.

The platinum miner based in South Africa had a particularly poor month in May, when half-year figures were affected by production disruptions, higher costs, and falling prices.

Over the past year, the shares are down 50%.

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Insurance disaster
Homeserve (LSE: HSV.L) has had 78.5 pence slashed off the price of its shares during the past three months, sending them tumbling 34% to 155 pence. And that comes after a massive fall last October, leading to an overall loss of around 70% over 12 months.

The firm, which specializes in domestic emergency insurance and covers things like blocked drains and boiler failures, was hit by an investigation into possible mis-selling of policies in October, and suspended all of its sales and marketing activities.

And it just hasn't recovered, with May's annual results leading to a further fall. Anyone want to take a punt on a possible 7% dividend yield for March 2013?

A contract gone bad
Cape (LSE: CIU.L) is our third casualty of the quarter, having had 166 pence slashed off the value of its shares, sending them down to 260 pence from 426 pence just three months ago -- that's a 39% slump.

The problem for Cape, which provides support services, principally to the energy and mineral resources sectors, was a project gone bad in Algeria. An announcement on May 25 that it was behind schedule and headed for a significant loss sent the shares down 122 pence on the day to 202 pence, a fall of 38%.

It's recovered a bit since then, and with a prospective price-to-earnings ratio of 6.3 and a forecasted dividend yield of 5.8%, might the fall be overdone?

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