NEW YORK ( TheStreet) -- Major coal companies like Patriot Coal ( PCX), International Coal Group ( ICO) and Westmoreland Coal ( WLB) outperformed other stocks past week, while silver stocks like Alexco Resources ( AXU), Silver Wheaton ( SLW) and Silver Standard Resources ( SSRI) eroded a significant portion of their stock value.The flooding disaster in Australia has dented coal supply, due to which prices are set to rise in the coming months, thereby boosting coal producers' profits worldwide. Exacerbating the concerns, South African coal shipments have also been delayed by the severe rain. Coal shortages and supply disruptions appear at time when global coal demand is on a roll. In such a scenario, coal stocks are a good buy. Moreover, BlackRock analyst Daniel Rice adds prices of coal stocks are likely to double as oil prices spike to nearly $100 a barrel, reported Bloomberg. Patriot Coal soared 19.7% last week after BB&T Capital Markets upgraded the stock's rating to buy from the earlier hold. Additionally, the industry is concerned that flooding in Australia could sustain U.S. coal exports. Moreover, as coal demand is forecast to grow robustly, an improved economic outlook in the U.S. cushions the demand for coal, which is essential for the development of other commodities. International Coal Group scaled up 11% after analysts at Dahlman Rose raised its target price to $12 from the earlier set $10. Meanwhile, rumors surfaced that Massey Energy ( MEE) is negotiating a potential takeover of ICO, thus seeking strategic alternatives for the company. If the two entities combine, the synergies from the deal may accelerate market competition. Massey is likely to benefit from International Coal's mining operations and reserves, which are strategically located to serve its client base of utility, metallurgical and industrial customers spread across eastern U.S., reported Trefis. Massey gained 4.6% after Dahlman Rose raised its target price to $67 from the earlier $48. Natural Resource Partners ( NRP) zoomed 5.5%. The stock was upgraded to an outperform rating from the earlier neutral rating. Meanwhile, another coal company Westmoreland Coal jumped 9.3% past week. After Dahlman Rose raised its price target to $74 from the earlier $52, Alpha Natural Resources ( ANR) accumulated 8.7% during the past one week.