Thursday was one of the worst sessions that the stock market has seen in several months, with major benchmarks falling 1% or more. Investors are growing increasingly nervous about the rising tensions between the Trump administration and North Korea, and skepticism about whether hoped-for domestic policy initiatives will actually take shape in Washington is also on the rise. Even amid difficult market conditions, some companies managed to enjoy good news that sent their shares higher. Pan American Silver (PAAS 1.14%), Chefs' Warehouse (CHEF 1.20%), and Perrigo (PRGO 1.49%) were among the best performers on the day. Below, we'll look more closely at these stocks to tell you why they did so well.

Pan American shines

Shares of Pan American Silver finished higher by 10.5% after the silver mining company reported its second-quarter financial results. Rising silver prices were partially responsible for earnings that were better than expected, but even more important was favorable commodity price action in zinc, which is one of the by-products of Pan American's silver production. The miner produced 13,700 metric tons of zinc during the quarter, and prices were up by a third compared to the year-earlier quarter, helping to support a big boost in the bottom line and a drop in all-in sustaining costs. Combine that with strength in precious metals today, and Pan American's big move upward makes plenty of sense.

Mining worker in a warehouse filled with boxes.

Image source: Pan American Silver.

Chefs' Warehouse satisfies investors

Chefs' Warehouse stock soared 19% in the wake of the company's financial report for the second quarter. Sales climbed 14% from the year-earlier quarter on double-digit percentage organic growth, and more favorable gross margin figures helped to make the company more internally efficient. Solid guidance for the remainder of the year also boosted shares of the stock. After having seen some challenges in past quarters, the specialty food company now appears to be moving forward with a more sustainable comeback for its business, and investors are reflecting their enthusiasm about Chefs' Warehouse's prospects going forward.

Perrigo holds up better than expected

Finally, shares of Perrigo finished higher by 16%. The drug company said that revenue in the second quarter fell 8% from year-ago levels, leading to a 5% reduction in adjusted net income for the period. Yet most of the negative impact on sales came from strategic divestitures, and the company boosted its adjusted earnings guidance for the full year by roughly 5%. In addition, private equity company SK Capital said that it had agreed to purchase Perrigo's active pharmaceutical ingredients business, with the agreement calling for supply contracts for Perrigo to continue getting essential ingredients. The deal could help Perrigo free up assets for use elsewhere in its business, and that would potentially be quite positive for the generic-drug specialist going forward.