Shares of U.S. Silica (SLCA) - Get Report drifted lower Tuesday after an analyst downgrade.

U.S. Silica's stock price fell 3.29% to $9.24 a share after Cowen lowered its rating on the key oil and gas industry supplier to market perform from outperform.

Cowen also cut its price target on the company, which produces commercial grade silica that is a crucial ingredient in the hydraulic fracking process, to $8.50 a share from $12 previously, according to Bloomberg.

Cowen analyst Marc Bianchi cited margin compression, limited free cash flow and concerns about the company's debt load in explaining the decision to downgrade U.S. Silica.

U.S. Silica saw cash and cash equivalents plunge 41.2% in the second quarter compared to same period in 2018, falling to $189.4 million, the company reported. The company also reported operating cash flow of $71.6 million during the quarter.

Long-term debt weighed in at more than $1.2 billion, or down 1.9% from the same quarter last year.

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