The FTSE 100 was marginally down on the last trading day of the week, resting at 6,615 amid a very quiet day for equity news. The market has rallied since late June but still trades below lofty heights seen in May. Next week's corporate announcements include results from GlaxoSmithKline (GSK), Unilever (ULVR), Rolls-Royce (RR.) and British Sky Broadcasting (BSY).

Worrying investors today is Sirius Minerals (SXX:AIM), down 16.7% to 18.75p after its engineering consultant AMEC (AMEC) put a dampener on the miner's proposed potash mine in Yorkshire. AMEC says there isn't a significant market for polyhalite, the product which Sirius hopes to sell, and therefore it will be hard to realise economic and job benefits from building the mine. Sirius refutes this statement, pointing to sales agreements that have already been made.

Irish support services group DCC (DCC) jumped 3% to £26.80 after raising its profit guidance for the year. The shares have enjoyed a strong rally over the past 12 months, helped by making London its primary listing and therefore improving stock liquidity - in addition to strong earnings growth.

Rig refurbishment and construction play Lamprell (LAM) gained 3.7% to 150.6p after finalising a debt refinancing deal. Having informed the market last month (17 Jun) it had secured binding commitment letters for the arrangement of a new lending facility, it has now signed a definite agreement.

Golden Saint Resources (GSR:AIM) jumped 20% to 12p on its first day of dealings on Aim. That means the aspiring diamond and gold miner is valued at £50.4 million which seems ludicrous given the very early-stage nature of its projects.

Ahead of joining Aim on 24 July, Plus500 has raised $75 million by placing $25 million new and $50 million of existing shares. The business runs an online trading platform for retail customers to trade contracts for difference. It is expected to be valued at $200 million on admission.

Diagnostic screening and testing device maker Akers Biosciences (AKR: AIM) improved 14.2% to 1.2p after its interim performance exceeded management?s revenue expectations. The company is set to record its maiden profit this year due a rise in demand for its disposable breathalysers following a French ruling that all cars must carry such a device at all times.

Property investor Development Securities (DSC) was up 2.6% to 203.5p following a positive market update. The company secured five planning consents between March and July 19 and complete further asset disposals putting it in a strong position to generate cash and make further gains in the year to March.

Shares in African agri-business Zambeef Products (ZAM:AIM) took a pounding, shedding 11% to 40.5p on an operational update. The £113 million cap's profits for the year are now likely to disappoint due to a combination of a food safety scare and lower than expected wheat prices. As a precautionary measure, Zambeef has removed all imported beef products from its retail outlets after sample tests indicated the presence of formaldehyde, while lower wheat prices will hit sales of its surplus wheat stocks.

Broker WH Ireland (WHI:AIM) fell 4.9% to 58.5p after chairman Rupert Lowe warned interim results did not fully reflect progress made during the half, including the acquisition of failed rival Seymour Pierce. Revenues rose 3.6% in the period to £13.1 million, on assets under management up 31.9% to £2.3 billion, but profits fell to just £59,000 from £185,000 a year earlier.

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Issue Date: 19 Jul 2013